Multidentate ligands and use thereof

ABSTRACT

Also provided are methods of preparing metal complexes from the multidentate ligand, and the metal complexes prepared by such methods. Further provided are catalysts comprising such metal complexes, and various uses of such catalysts.

CROSS REFERENCE TO RELATED APPLICATIONS

The present application claims benefit of U.S. Provisional PatentApplication Ser. No. 62/646,062, filed on Mar. 21, 2018 whichapplication is incorporated by reference herein in its entirety.

GOVERNMENT FUNDING

This invention was made with government support under grant nos.CHE-1058987 and CHE-1465095, awarded by NSF, and grant no.DE-FG02-93ER14339, awarded by Department of Energy (DOE). The governmenthas certain rights in the invention.

FIELD OF INVENTION

The present invention provides, inter alia, multidentate ligand havingthe structure:

Also provided are metal complexes generated by the ligands of thepresent invention, as well as methods of using such ligands andcomplexes.

BACKGROUND OF THE INVENTION

Despite their paucity, terminal metal hydride compounds offer muchpotential, and are often invoked as intermediates in a variety ofcatalytic cycles, including hydrosilylation, hydroboration,hydroamination, and hydrogenation (Harder 2012; Sarish et al 2011;Rochat et al 2016; Hill et al 2016; Arrowsmith 2015; Crimmin et al 2013;Revunova et al 2015; Dunne et al 2011; Schnitzler et al 2016; Spielmannet al 2008; Buch et al 2006). Such transformations offer potentialsocietal benefits, especially considering that, for example, industrialhydrosilylation reactions typically employ precious metal catalysts(Meister et al 2016).

Also, the efficient utilization of carbon dioxide as a renewable C₁source for the synthesis of value-added organic chemicals and fuels isnot only of intrinsic value, but also offers potential for abating theincreasing levels of carbon dioxide in the atmosphere (Aresta 2010; Liuet al 2015; Fraga et al 2015). However, CO₂ is thermodynamically verystable and kinetically resistant to many transformations, which presentsa major impediment to achieving this objective.

Accordingly, there is a need for the exploration of various terminalmetal hydride compounds that can be used in catalytic systems forhydrosilylation, hydroboration, hydroamination and hydrogenation thatemploy non-precious metals, occur at room temperature, and may bemodified to control the level of reduction. This invention is directedto meet these and other needs.

SUMMARY OF THE INVENTION

One embodiment of the present invention is a compound multidentateligand having the structure of formula (I):

wherein:

-   -   Z is a linker group;    -   R₁ is selected from the group consisting of H, halide, alkyl,        aryl, aralkyl, heteroalkyl, heteroaryl, alkoxy, hydroxy,        heteroalkoxy, amino, alkylamino, arylamino, cyano, nitro,        sulfonyl, or a heterocyclic group;    -   R₂ and R₃ are independently selected from the group consisting        of H, halide, alkyl, aryl, aralkyl, heteroalkyl, heteroaryl,        alkoxy, hydroxy, heteroalkoxy, amino, alkylamino, arylamino,        cyano, nitro, sulfonyl, or a heterocyclic group; or together        form a saturated or unsaturated C₅₋₇ homocyclic or heterocyclic        ring, wherein the ring is optionally substituted with groups        selected from H, halide, alkyl, aryl, aralkyl, heteroalkyl,        heteroaryl, alkoxy, hydroxy, heteroalkoxy, amino, alkylamino,        arylamino, cyano, nitro, sulfonyl, or a heterocyclic group.

Another embodiment of the present invention is a multidentate ligandhaving the following structure:

Another embodiment of the present invention is a method of preparing ametal complex. This method comprises coordinating a ligand disclosedherein to a metal center via a combination of up to three nitrogendonors and a carbon atom.

Another embodiment of the present invention is a metal complex preparedby a method disclosed herein. The metal complex has the structure offormula (II):

wherein:

-   -   M is an atom selected from Li, Mg, Ca, Fe, Ni, Cu, Zn, Zr and        Cd; and    -   X is selected from no atom, H, Me, halogen, O₂CH, S₂CH, SH,        N(H)Ph, CH(Me)Ph, O₂CMe and S₂CMe.

Another embodiment of the present invention is a metal complex preparedby a method disclosed herein. The metal complex has the followingstructure:

Another embodiment of the present invention is a metal complex preparedby a method disclosed herein. The metal complex has the followingstructure:

Another embodiment of the present invention is a catalyst. The catalystcomprises at least one metal complex disclosed herein.

Another embodiment of the present invention is a method of catalyzinghydrosilylation of styrenes. This method comprises providing a catalystdisclosed herein to a hydrosilylation reaction of a styrene.

Another embodiment of the present invention is a method of catalyzinghydroboration of styrenes. This method comprises providing a catalystdisclosed herein to a hydroboration reaction of a styrene.

Another embodiment of the present invention is a method of catalyzinghydrosilylation of carbon dioxide. This method comprises providing acatalyst disclosed herein to a hydrosilylation reaction of carbondioxide.

Another embodiment of the present invention is a method of preparing aformaldehyde equivalent from carbon dioxide. This method comprisescontacting a reaction mixture comprising carbon dioxide and a silanewith a compound prepared from a multidentate ligand disclosed herein,wherein the silane is R₃SiH and R is selected from H, alkyl and aryl.

A further embodiment of the present invention is a method of reducingcarbon monoxide. This method comprises contacting a reaction mixturecomprising carbon monoxide with a compound prepared from a multidentateligand disclosed herein.

Another embodiment of the present invention is a method of catalyzinghydrogenation of alkenes or alkynes. This method comprises providing acatalyst disclosed herein to a hydrogenation reaction of an alkene or analkyne.

Another embodiment of the present invention is a method of catalyzingpolymerization of alkenes. This method comprises providing a catalystdisclosed herein to a polymerization reaction of alkenes.

Another embodiment of the present invention is a method of catalyzingproduction of hydrogen-on-demand from alcohols or amines. This methodcomprises providing a catalyst disclosed herein to the reaction.

Another embodiment of the present invention is a method of catalyzinghydrosilylation of ketones or aldehydes. This method comprises providinga catalyst disclosed herein to a hydrosilylation reaction of a ketone oran aldehyde.

Another embodiment of the present invention is a method of catalyzingTishchenko reaction. This method comprises providing a catalystdisclosed herein to the reaction.

Another embodiment of the present invention is a method of catalyzinghydrogenation of carbon dioxide. This method comprises providing acatalyst disclosed herein to a hydrogenation reaction of carbon dioxide.

Another embodiment of the present invention is a method of catalyzinghydrogenation of carbon monoxide. This method comprises providing acatalyst disclosed herein to a hydrogenation reaction of carbonmonoxide.

BRIEF DESCRIPTION OF THE DRAWINGS

The application file contains at least one photograph executed in color.Copies of this patent application with color photographs will beprovided by the Office upon request and payment of the necessary fee.

DETAILED DESCRIPTION OF THE INVENTION

In the present invention, multidentate ligands and metal complexesprepared from the same are provided. Certain of the metal complexes canbe used in catalytic systems for hydrosilylation, hydroboration,hydroamination and hydrogenation. Accordingly, one aspect of the presentinvention is a multidentate ligand having the structure of formula (I):

wherein:

-   -   Z is a linker group;    -   R₁ is selected from the group consisting of H, halide, alkyl,        aryl, aralkyl, heteroalkyl, heteroaryl, alkoxy, hydroxy,        heteroalkoxy, amino, alkylamino, arylamino, cyano, nitro,        sulfonyl, or a heterocyclic group;    -   R₂ and R₃ are independently selected from the group consisting        of H, halide, alkyl, aryl, aralkyl, heteroalkyl, heteroaryl,        alkoxy, hydroxy, heteroalkoxy, amino, alkylamino, arylamino,        cyano, nitro, sulfonyl, or a heterocyclic group; or together        form a saturated or unsaturated C₅₋₇ homocyclic or heterocyclic        ring, wherein the ring is optionally substituted with groups        selected from H, halide, alkyl, aryl, aralkyl, heteroalkyl,        heteroaryl, alkoxy, hydroxy, heteroalkoxy, amino, alkylamino,        arylamino, cyano, nitro, sulfonyl, or a heterocyclic group.

In some embodiments, the linker group Z comprises a silicon-containinggroup.

In some embodiments, the linker group Z is Si(R₄)₂; and wherein R₄ isselected from the group consisting of H, halide, alkyl, aryl, aralkyl,heteroalkyl, heteroaryl, alkoxy, hydroxy, heteroalkoxy, amino,alkylamino, arylamino, cyano or a heterocyclic group.

Preferably, the multidentate ligand of this embodiment has the followingstructure:

Another embodiment of the present invention is method of preparing ametal complex. This method comprises coordinating a ligand disclosedherein to a metal center via a combination of up to three nitrogendonors and a carbon atom.

Preferably, the metal center comprises an atom selected from the maingroup metals, transition metals, or lanthanoids.

More preferably, the metal center comprises an atom selected from Li,Mg, Ca, Fe, Ni, Cu, Zn, Zr and Cd.

Another aspect of the present invention is a metal complex prepared by amethod disclosed herein. The metal complex has the structure of formula(II):

wherein:

-   -   M is an atom selected from Li, Mg, Ca, Fe, Ni, Cu, Zn, Zr and        Cd; and    -   X is selected from no atom, H, Me, halogen, O₂CH, S₂CH, SH,        N(H)Ph, CH(Me)Ph, O₂CMe and S₂CMe.

Preferably, the metal complex has a structure selected from the groupconsisting of:

More preferably, the metal complex has the following structure:

More preferably, the metal complex has the following structure:

Another aspect of the present invention is a catalyst. The catalystcomprises at least one metal complex disclosed herein.

Another aspect of the present invention is a method of catalyzinghydrosilylation of styrenes. This method comprises providing a catalystdisclosed herein to a hydrosilylation reaction of a styrene.

Another aspect of the present invention is a method of catalyzinghydroboration of styrenes. This method comprises providing a catalystdisclosed herein to a hydroboration reaction of a styrene.

Another aspect of the present invention is a method of catalyzinghydrosilylation of carbon dioxide. This method comprises providing acatalyst disclosed herein to a hydrosilylation reaction of carbondioxide.

Still another aspect of the present invention is a method of preparing aformaldehyde equivalent from carbon dioxide. This method comprisescontacting a reaction mixture comprising carbon dioxide and a silanewith a compound prepared from a multidentate ligand disclosed herein,wherein the silane is R₃SiH and R is selected from H, alkyl and aryl.

In some embodiments, the multidentate ligand has the structure:

In some embodiments, the compound comprises at least one metal complexdisclosed herein.

A further aspect of the present invention is a method of reducing carbonmonoxide. This method comprises contacting a reaction mixture comprisingcarbon monoxide with a compound prepared from a multidentate liganddisclosed herein.

In some embodiments, the multidentate ligand has the structure:

In some embodiments, the compound comprises at least one metal complexdisclosed herein.

Another aspect of the present invention is a method of catalyzinghydrogenation of alkenes or alkynes. This method comprises providing acatalyst disclosed herein to a hydrogenation reaction of an alkene or analkyne.

Another aspect of the present invention is a method of catalyzingpolymerization of alkenes. This method comprises providing a catalystdisclosed herein to a polymerization reaction of alkenes.

Another aspect of the present invention is a method of catalyzingproduction of hydrogen-on-demand from alcohols or amines. This methodcomprises providing a catalyst disclosed herein to the reaction.

Another aspect of the present invention is a method of catalyzinghydrosilylation of ketones or aldehydes. This method comprises providinga catalyst disclosed herein to a hydrosilylation reaction of a ketone oran aldehyde.

Another aspect of the present invention is a method of catalyzingTishchenko reaction. This method comprises providing a catalystdisclosed herein to the reaction.

Another aspect of the present invention is a method of catalyzinghydrogenation of carbon dioxide. This method comprises providing acatalyst disclosed herein to a hydrogenation reaction of carbon dioxide.

Another aspect of the present invention is a method of catalyzinghydrogenation of carbon monoxide. This method comprises providing acatalyst disclosed herein to a hydrogenation reaction of carbonmonoxide.

In the foregoing embodiments, the following definitions apply.

The term “alkyl” refers to the radical of saturated aliphatic groupsthat does not have a ring structure, including straight-chain alkylgroups, and branched-chain alkyl groups. In certain embodiments, astraight chain or branched chain alkyl has 6 or fewer carbon atoms inits backbone (e.g., C₁-C₆ for straight chains, C₃-C₆ for branchedchains). Such substituents include all those contemplated for aliphaticgroups, as discussed below, except where stability is prohibitive.

The term “alkoxy”, as used herein, refers to an alkyl (carbon andhydrogen chain) group singularly bonded to oxygen; thus R—O. Related toalkoxy groups are aryloxy groups, which have an aryl group singularbonded to oxygen such as the phenoxy group (C₆H₅O—).

The term “alkene” or “olefin”, as used herein, refers to an unsaturatedhydrocarbon that contains at least one carbon-carbon double bond.

The term “alkyne”, as used herein, refers to an unsaturated hydrocarboncontaining at least one carbon-carbon triple bond.

The term “alkenyl”, as used herein, refers to an aliphatic groupcontaining at least one double bond and unless otherwise indicated, isintended to include both “unsubstituted alkenyls” and “substitutedalkenyls”, the latter of which refers to alkenyl moieties havingsubstituents replacing a hydrogen on one or more carbons of the alkenylgroup. Such substituents include all those contemplated for aliphaticgroups, as discussed below, except where stability is prohibitive. Forexample, substitution of alkenyl groups by one or more alkyl,carbocyclyl, aryl, heterocyclyl, or heteroaryl groups is contemplated.

Moreover, unless otherwise indicated, the term “alkyl” as usedthroughout the specification, examples, and claims is intended toinclude both “unsubstituted alkyls” and “substituted alkyls”, the latterof which refers to alkyl moieties having substituents replacing ahydrogen on one or more carbons of the hydrocarbon backbone. Indeed,unless otherwise indicated, all groups recited herein are intended toinclude both substituted and unsubstituted options.

The term “C_(x-y)” when used in conjunction with a chemical moiety, suchas, alkyl and cycloalkyl, is meant to include groups that contain from xto y carbons in the chain. For example, the term “C_(x-y)alkyl” refersto substituted or unsubstituted saturated hydrocarbon groups, includingstraight-chain alkyl and branched-chain alkyl groups that contain from xto y carbons in the chain, including haloalkyl groups such astrifluoromethyl and 2,2,2-trifluoroethyl, etc.

The term “aryl” as used herein includes substituted or unsubstitutedsingle-ring aromatic groups in which each atom of the ring is carbon.Preferably the ring is a 3- to 8-membered ring, more preferably a6-membered ring. The term “aryl” also includes polycyclic ring systemshaving two or more cyclic rings in which two or more carbons are commonto two adjoining rings wherein at least one of the rings is aromatic,e.g., the other cyclic rings can be cycloalkyls, cycloalkenyls,cycloalkynyls, aryls, heteroaryls, and/or heterocyclyls. Aryl groupsinclude benzene, naphthalene, phenanthrene, phenol, aniline, and thelike.

The term “alkyl-aryl” or “aralkyl” refers to an alkyl group substitutedwith at least one aryl group.

The term “alkyl-heteroaryl” refers to an alkyl group substituted with atleast one heteroaryl group.

The term “alkenyl-aryl” refers to an alkenyl group substituted with atleast one aryl group.

The term “alkenyl-heteroaryl” refers to an alkenyl group substitutedwith at least one heteroaryl group.

The term “amino,” as used herein, alone or in combination, refers to—NRR′, wherein R and R′ are independently chosen from hydrogen, alkyl(i.e., alkylamino), acyl, heteroalkyl, aryl (i.e., arylamino),cycloalkyl, heteroaryl, and heterocycloalkyl, any of which maythemselves be optionally substituted. Additionally, R and R′ may combineto form heterocycloalkyl, either of which may be optionally substituted.

The term “amine”, as used herein, refers to a compound or a functionalgroup that contains a basic nitrogen atom with a lone pair. Amines areformally derivatives of ammonia, where in one or more hydrogen atomshave been replaced by a substituent such as an alkyl or aryl group(these may respectively be called alkylamines and arylamines; amines inwhich both types of substituent are attached to one nitrogen atom may becalled alkylarylamines).

The term “cyano,” as used herein, alone or in combination, refers to—CN.

The term “sulfonyl”, as used herein, alone or in combination, referseither to a functional group found primarily in sulfones or to asubstituent obtained from a sulfonic acid by the removal of the hydroxylgroup similarly to acyl groups. Sulfonyl groups can be written as havingthe general formula R—S(═O)2-R′, where there are two double bondsbetween the sulfur and oxygen.

The term “alcohol” means an organic compound in which the hydroxylfunctional group (—OH) is bound to a saturated carbon atom.

The term “ketone” means an organic compound with the structure RC(═O)R′,wherein neither R and R′ can be hydrogen atoms.

The term “aldehyde” or “alkanal” means an organic compound containing afunctional group with the structure —CHO, consisting of a carbonylcenter (a carbon double-bonded to oxygen) with the carbon atom alsobonded to hydrogen and to an R group, which is any generic alkyl or sidechain. The group (without R) is the aldehyde group, also known as theformyl group.

The term “cycloalkyl,” or, alternatively, “carbocycle,” as used herein,alone or in combination, refers to a saturated or partially saturatedmonocyclic, bicyclic or tricyclic alkyl group wherein each cyclic moietycontains from 3 to 12 carbon atom ring members and which may optionallybe a benzo fused ring system which is optionally substituted as definedherein. In certain embodiments, said cycloalkyl will comprise from 5 to7 carbon atoms. Examples of such cycloalkyl groups include cyclopropyl,cyclobutyl, cyclopentyl, cyclohexyl, cycloheptyl, tetrahydronaphthyl,indanyl, octahydronaphthyl, 2,3-dihydro-1H-indenyl, adamantyl and thelike. “Bicyclic” and “tricyclic” as used herein are intended to includeboth fused ring systems, such as decahydronaphthalene,octahydronaphthalene as well as the multicyclic (multicentered)saturated or partially unsaturated type. The latter type of isomer isexemplified in general by, bicyclo[1,1,1]pentane, camphor, adamantane,and bicyclo[3,2,1]octane.

The term “heteroatom” as used herein means an atom of any element otherthan carbon or hydrogen. Preferred heteroatoms are nitrogen, oxygen, andsulfur; more preferably, nitrogen and oxygen.

The term “heteroalkyl,” as used herein, alone or in combination, refersto a stable straight or branched chain, or cyclic hydrocarbon radical,or combinations thereof, fully saturated or containing from 1 to 3degrees of unsaturation, consisting of the stated number of carbon atomsand from one to three heteroatoms chosen from 0, N, and S, and whereinthe nitrogen and sulfur atoms may optionally be oxidized and thenitrogen heteroatom may optionally be quaternized. The heteroatom(s) O,N and S may be placed at any interior position of the heteroalkyl group.

The term “heteroaryl” includes substituted or unsubstituted aromaticsingle ring structures, preferably 3- to 8-membered rings, morepreferably 5- to 7-membered rings, even more preferably 5- to 6-memberedrings, whose ring structures include at least one heteroatom, preferablyone to four heteroatoms, more preferably one or two heteroatoms. Theterm “heteroaryl” also includes polycyclic ring systems having two ormore cyclic rings in which two or more carbons are common to twoadjoining rings wherein at least one of the rings is heteroaromatic,e.g., the other cyclic rings can be cycloalkyls, cycloalkenyls,cycloalkynyls, aryls, heteroaryls, and/or heterocyclyls. Heteroarylgroups include, for example, pyrrole, furan, thiophene, imidazole,oxazole, thiazole, pyrazole, pyridine, pyrazine, pyridazine, andpyrimidine, and the like.

The terms “heterocycloalkyl” and, interchangeably, “heterocycle,” asused herein, alone or in combination, each refer to a saturated,partially unsaturated, or fully unsaturated monocyclic, bicyclic, ortricyclic heterocyclic group containing at least one heteroatom as aring member, wherein each said heteroatom may be independently chosenfrom N, O, and S. Additionally, a heterocycloalkyl may contain one ortwo C(O), S(O), or S(O)₂ groups as ring members. In certain embodiments,said heterocycloalkyl will comprise from 1 to 4 heteroatoms as ringmembers. In further embodiments, said heterocycloalkyl will comprisefrom 1 to 2 heteroatoms as ring members. In certain embodiments, saidheterocycloalkyl will comprise from 3 to 8 ring members in each ring. Infurther embodiments, said heterocycloalkyl will comprise from 3 to 7ring members in each ring. In yet further embodiments, saidheterocycloalkyl will comprise from 5 to 6 ring members in each ring.“Heterocycloalkyl” and “heterocycle” are intended to include sulfones,sulfoxides, N-oxides of tertiary nitrogen ring members, and carbocyclicfused and benzo fused ring systems; additionally, both terms alsoinclude systems where a heterocycle ring is fused to an aryl group, asdefined herein, or an additional heterocycle group. Examples ofheterocycle groups include aziridinyl, azetidinyl, 1,3-benzodioxolyl,dihydroisoindolyl, dihydroisoquinolinyl, dihydrocinnolinyl,dihydrobenzodioxinyl, dihydro[1,3]oxazolo[4,5-b]pyridinyl,benzothiazolyl, dihydroindolyl, dihy-dropyridinyl, 1,3-dioxanyl,1,4-dioxanyl, 1,3-dioxolanyl, isoindolinyl, morpholinyl, piperazinyl,pyrrolidinyl, tetrahydropyridinyl, piperidinyl, thiomorpholinyl, and thelike. The heterocycle groups may be optionally substituted unlessspecifically prohibited.

The term “hydroxy,” as used herein, alone or in combination, refers to—OH.

The terms “halo” and “halogen” are used interchangeably herein and meanhalogen and include chloro, fluoro, bromo, and iodo.

The term “halide”, as used herein, refers to a binary phase, of whichone part is a halogen atom and the other part is an element or radicalthat is less electronegative (or more electropositive) than the halogen,to make a fluoride, chloride, bromide, or iodide compound. The alkalimetals combine directly with halogens under appropriate conditionsforming halides of the general formula, MX (X═F, Cl, Br or I).

The term “haloalkoxy,” as used herein, alone or in combination, refersto a haloalkyl group attached to the parent molecular moiety through anoxygen atom. Haloalkoxy includes perhaloalkoxy. The term “perhaloalkoxy”refers to an alkoxy group where all of the hydrogen atoms are replacedby halogen atoms. An example of perhaloalkoxy is perfluoromethoxy.

The term “haloalkyl,” as used herein, alone or in combination, refers toan alkyl radical having the meaning as defined above wherein one or morehydrogens are replaced with a halogen. Specifically embraced aremonohaloalkyl, dihaloalkyl, polyhaloalkyl, and perhaloalkyl radicals. Amonohaloalkyl radical, for one example, may have an iodo, bromo, chloroor fluoro atom within the radical. Dihalo and polyhaloalkyl radicals mayhave two or more of the same halo atoms or a combination of differenthalo radicals. Examples of haloalkyl radicals include fluoromethyl,difluoromethyl, trifluoromethyl, chloromethyl, dichloromethyl,trichloromethyl, pentafluoroethyl, heptafluoropropyl,difluorochloromethyl, dichlorofluoromethyl, difluoroethyl,difluoropropyl, dichloroethyl and dichloropropyl. “Haloalkylene” refersto a haloalkyl group attached at two or more positions. Examples ofhaloalkyl radicals include fluoromethyl, difluoromethyl,trifluoromethyl, chloromethyl, dichloromethyl, trichloromethyl,pentafluoroethyl, heptafluoropropyl, difluorochloromethyl,dichlorofluoromethyl, difluoroethyl, difluoropropyl, dichloroethyl anddichloropropyl. “Haloalkylene” refers to a haloalkyl group attached attwo or more positions. Examples include fluoromethylene (—CFH—),difluoromethylene (—CF₂—), chloromethylene (—CHCl—) and the like. Theterm “perhaloalkyl” as used herein, alone or in combination, refers toan alkyl group where all of the hydrogen atoms are replaced by halogenatoms. Examples include perfluoromethyl.

The term “nitro,” as used herein, alone or in combination, refers to—NO₂.

The term “substituted” refers to moieties having substituents replacinga hydrogen on one or more carbons of the backbone. It will be understoodthat “substitution” or “substituted with” includes the implicit provisothat such substitution is in accordance with the permitted valence ofthe substituted atom and the substituent, and that the substitutionresults in a stable compound, e.g., which does not spontaneously undergotransformation such as by rearrangement, cyclization, elimination, etc.As used herein, the term “substituted” is contemplated to include allpermissible substituents of organic compounds. In a broad aspect, thepermissible substituents include acyclic and cyclic, branched andunbranched, carbocyclic and heterocyclic, aromatic and non-aromaticsubstituents of organic compounds. The permissible substituents can beone or more and the same or different for appropriate organic compounds.For purposes of this invention, the heteroatoms such as nitrogen mayhave hydrogen substituents and/or any permissible substituents oforganic compounds described herein which satisfy the valences of theheteroatoms. Substituents can include any substituents described herein,for example, a halogen, a hydroxyl, a carbonyl (such as a carboxyl, analkoxycarbonyl, a formyl, or an acyl), a thiocarbonyl (such as athioester, a thioacetate, or a thioformate), an alkoxyl, a phosphoryl, aphosphate, a phosphonate, a phosphinate, an amino, an amido, an amidine,an imine, a cyano, a nitro, an azido, a sulfhydryl, an alkylthio, asulfate, a sulfonate, a sulfamoyl, a sulfonamido, a sulfonyl, aheterocyclyl, an aralkyl, or an aromatic or heteroaromatic moiety. Itwill be understood by those skilled in the art that the moietiessubstituted on the hydrocarbon chain can themselves be substituted, ifappropriate.

As set forth previously, unless specifically stated as “unsubstituted,”references to chemical moieties herein are understood to includesubstituted variants. For example, reference to an “aryl” group ormoiety implicitly includes both substituted and unsubstituted variants.

It is understood that the disclosure of a compound herein encompassesall stereoisomers of that compound. As used herein, the term“stereoisomer” refers to a compound made up of the same atoms bonded bythe same bonds but having different three-dimensional structures whichare not interchangeable. The three-dimensional structures are calledconfigurations. Stereoisomers include enantiomers and diastereomers.

The following examples are provided to further illustrate the methods ofthe present invention. These examples are illustrative only and are notintended to limit the scope of the invention in any way.

EXAMPLES

The invention is further illustrated by the following examples, whichare offered for illustrative purposes, and are not intended to limit theinvention in any manner. Those of skill in the art will readilyrecognize a variety of noncritical parameters, which can be changed ormodified to yield essentially the same results.

Example 1 Methods and Materials General Considerations

All manipulations were performed using a combination of glovebox, highvacuum, and Schlenk techniques under an argon atmosphere. Solvents werepurified and degassed by standard procedures.

¹H NMR chemical shifts are reported in ppm relative to SiMe4 (δ=0) andwere either referenced directly (for C₆D₅Br) or with respect to theprotio solvent impurity (δ=7.16 for C₆D₅H, δ=2.08 for toluene-d₈). ¹³CNMR spectra are reported in ppm relative to SiMe4 (δ=0) and werereferenced internally with respect to the solvent (δ=128.06 for C₆D₆,δ=128.06 for C₆D₅H, δ=20.43 for toluene-d₈). ⁷Li NMR are reported in ppmrelative to LiCl (δ=0) and were obtained by using the

/100% value of 38.863797. ¹⁹F NMR chemical shifts are reported in ppmrelative to CFCl₃ (δ=0.0) and were obtained by using the

/100% value of 94.094011. ²⁹Si NMR chemical shifts are reported in ppmrelative to SiMe4 (δ=0.0) and were obtained by using the

/100% value of 19.867187. ¹¹B NMR chemical shifts are reported in ppmrelative to BF₃.OEt₂ and were obtained by using the

/100% value of 32.083974. Coupling constants are given in hertz.Infrared spectra were recorded on a Perkin Elmer Spectrum Twospectrometer in attenuated total reflectance (ATR) mode, or a ThermoScientifc Nicolet FT-IR 6700 spectrometer with a liquid N₂ cooled MCT-Adetector, and are reported in reciprocal centimeters.

1-isopropylbenzimidazole, HC(SiMe₂Cl)₃, Me₂Mg, [Me₃PCuCl]₄, [Tism^(Pr)^(i) ^(Benz)]MgMe, [Tism^(Pr) ^(i) ^(Benz)]Li, [Tism^(Pr) ^(i)^(Benz)]MgH, Me₃SnF and Me₃SnI were obtained by literature methods andBu^(n)Li (Aldrich), MeLi (Aldrich), Me₂Zn (Aldrich), (Ph₃P)₂NiBr₂(Strem), PhSiH₃, pinacolborane, CO₂, CS₂, PhNH₂, H₂S, styrene,N,N′-dicyclohexylcarbodiimide, N,N′-diisopropylcarbodiimide, pyridine,TEMPO (Sigma Aldrich), Me₃SnCl (Strem Chemicals), Me₃SnBr (Alfa Aesar),KOSiMe₃ (90%), ZnBr₂, Et₃SiH, ¹³CO₂ (Cambridge Isotopes Laboratories)and Ph₃SiH (Alfa Aesar) were obtained commercially and used as received.

X-Ray Structure Determinations

X-ray diffraction data were collected on a Bruker Apex IIdiffractometer. The structures were solved by using direct methods andstandard difference map techniques, and were refined by full-matrixleast-squares procedures on F2 with SHELXTL (Version 2014/7).

Example 2 Synthesis of Multidentate Ligands and Metal Complexes

The synthesis of multidentate ligands and various metal complexes andtheir derivatives are described below in detail.

Preparation of [Tism^(Pr) ^(i) ^(Benz)]Li

The volatile components of a solution of MeLi in Et₂O (56.8 mmol, 35.5mL of 1.6 M) were removed in vacuo and the solid obtained was dissolvedin THF (ca 50 mL). The solution was treated slowly with distilled1-isopropylbenzimidazole (8.81 g, 55 mmol) over a period of 10 minutes,and stirred for an additional 20 minutes. After this period, thevolatile components were removed in vacuo to give an orange oil. Pentane(ca 30 mL) was added and the mixture was stirred for 10 minutes, afterwhich period the volatile components were removed in vacuo to afford alight orange foam-like solid. The solid was dissolved in benzene (ca 30mL) and the solution was added to a glass pressure vessel containingsolid MeLi as obtained by the removal of volatile components in vacuofrom a solution of MeLi in Et₂O (18.9 mmol, 11.8 mL of 1.6 M). Theresulting orange suspension was placed in an ice bath and was treatedslowly with a solution of freshly distilled HC(SiMe₂Cl)₃ (5.4 g, 18.4mmol) in benzene (ca 20 mL) over a period of ca. 15 minutes. The mixturewas allowed to warm to room temperature and stirred until gas evolutionceased (ca 1 hour), after which period the vessel was sealed and stirredat 100° C. for 15 hours. Benzene (ca 40 mL) was added to the resultingred mixture, and the fine precipitate was allowed to settle and thesolution was decanted. This process was repeated with two portions ofbenzene (ca 40 mL) and the combined extracts were concentrated in vacuoto a volume of ca 20 mL, thereby resulting in the deposition of a solidover a period of two days. The solid was isolated by filtration, washedwith Et₂O (2×ca 20 mL), and dried in vacuo to afford [Tism^(Pr) ^(i)^(Benz)]Li as an off-white powder, (5.1 g, 41% yield). Colorlesscrystals of [Tism^(Pr) ^(i) ^(Benz)]Li suitable for X-ray diffractionwere obtained by slow evaporation of a solution in benzene.

¹H NMR (C₆D₆):

0.63 [s, 18H, (C₆H₄N₂CH(CH₃)₂CSi(CH ₃)₂)₃CLi],

1.23 [d, J=7 Hz, 18H, (C₆H₄N₂CH(CH ₃)₂CSi(CH₃)₂)₃CLi],

4.84 [sept, J=7 Hz, 3H, (C₆H₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CLi],

7.06 [m, 6H, (C₆ H ₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CLi],

7.28 [m, 3H, (C₆ H ₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CLi],

8.00 [m, 3H, (C₆ H ₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CLi].

¹³C NMR (C₆D₆):

6.23 [s, 6C, (C₆H₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CLi],

21.18 [s, 6C, (C₆H₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CLi],

49.40 [s, 3C, (C₆H₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CLi],

112.73 [s, 3C, (C₆H₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CLi],

119.78 [s, 3C, (C₆H₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CLi],

121.91 [s, 3C, (C₆H₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CLi],

121.96 [s, 3C, (C₆H₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CLi],

134.21 [s, 3C, (C₆H₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CLi],

145.52 [s, 3C, (C₆H₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CLi],

169.31 [s, 3C, (C₆H₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CLi],

not observed [(C₆H₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CLi].

²⁹Si NMR (C₆D₆): −14.48 [s, (C₆H₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CLi].

⁷Li NMR (C₆D₆): 5.32.

Anal. calc. for [Tism^(Pr) ^(i) ^(Benz)]Li: C, 66.2%; H, 7.7%; N, 12.5%.Found: C, 66.5%; H, 7.4%; N, 12.3%.

IR Data (cm⁻¹): 3053 (w), 2964 (w), 2949 (w), 1463 (m), 1389 (w), 1371(w), 1341 (m), 1320 (w), 1282 (m), 1159 (w), 1106 (w), 1061 (m), 964(vs), 821 (s), 791 (s), 737 (vs), 672 (s).

Preparation of [Tism^(Pr) ^(i) ^(Benz)]H

H₂O (40 μL, 2.22 mmol) was added to a solution of [Tism^(Pr) ^(i)^(Benz)]Li (640 mg, 0.954 mmol) in benzene (ca 25 mL). The mixture wasstirred for 1 hour at room temperature, during which period aprecipitate formed. The volatile components were removed in vacuo andthe residue obtained was extracted into benzene (ca 25 mL). The solventwas removed from the extract in vacuo resulting in [Tism^(Pr) ^(i)^(Benz)]H as a white powder (610 mg, 96% yield). Colorless crystals of[Tism^(Pr) ^(i) ^(Benz)]H suitable for X-ray diffraction were obtainedvia slow evaporation of a benzene solution.

¹H NMR (C₆D₆):

0.55 [s, 18H, (C₆H₄N₂CH(CH₃)₂CSi(CH ₃)₂)₃CH],

1.40 [d, J=7 Hz, 18H, (C₆H₄N₂CH(CH ₃)₂CSi(CH₃)₂)₃CH],

2.30 [s, 1H, (C₆H₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CH],

5.09 [sep, J=7 Hz, 3H, (C₆H₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CH],

7.14-7.23 [m, 6H, (C₆ H ₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CH],

7.38 [d, J=8 Hz, 3H, (C₆ H ₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CH],

8.04 [d, J=8 Hz, 3H, (C₆ H ₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CH].

¹³C{¹H} NMR (C₆D₆):

−1.22 [s, 1C, (C₆H₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CH],

1.89 [s, 6C, (C₆H₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CH],

21.49 [s, 6C, (C₆H₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CH],

49.85 [s, 3C, (C₆H₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CH],

112.69 [s, 3C, (C₆H₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CH],

121.13 [s, 3C, (C₆H₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CH],

121.73 [s, 3C, (C₆H₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CH],

122.49 [s, 3C, (C₆H₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CH],

134.84 [s, 3C, (C₆H₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CH],

146.98 [s, 3C, (C₆H₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CH],

159.75 [s, 3C, (C₆H₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CH].

²⁹Si NMR (C₆D₆): −7.32 [s, 3Si, (C₆H₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CH].

IR Data (cm⁻¹): 2979 (w), 1459 (m), 1394 (w), 1340 (s), 1321 (m), 1266(m) 1162 (w), 1131 (w) 1105 (w), 1060 (m), 1014 (m), 834 (s), 820 (vs),775 (s), 740 (vs), 681 (vs).

Conversion of [Tism^(Pr) ^(i) ^(Benz)]H to [Tism^(Pr) ^(i) ^(Benz)]Li

A solution of [Tism^(Pr) ^(i) ^(Benz)]H (30 mg, 0.045 mmol) in THF (ca 2mL) was treated with Bu^(n)Li (0.05 mL, 1.6 M in hexanes). The mixturewas stirred for one hour, during which period the solution turned lightorange. The volatile components were removed in vacuo and the formationof [Tism^(Pr) ^(i) ^(Benz)]Li was demonstrated by ¹H NMR spectroscopy.

Preparation of [Tism^(Pr) ^(i) ^(Benz)]MgMe

A solution of [Tism^(Pr) ^(i) ^(Benz)]H (400 mg, 0.601 mmol) in benzene(ca 20 mL) was treated with Me₂Mg (40 mg, 0.736 mmol). The mixture wasstirred for 20 minutes, after which the mixture was filtered and thefiltrate was lyophilized to afford [Tism^(Pr) ^(i) ^(Benz)]MgMe as awhite powder (405 mg, 96% yield). Colorless crystals of [Tism^(Pr) ^(i)^(Benz)]MgMe suitable for X-ray diffraction were obtained via slowevaporation of a benzene solution.

¹H NMR (C₆D₆):

0.20 [s, 3H, (C6H₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CMgCH ₃],

0.45 [s, 18H, (C₆H₄N₂CH(CH₃)₂CSi(CH ₃)₂)₃CMgCH₃],

1.16 [d, J=7 Hz, 18H, (C₆H₄N₂CH(CH ₃)₂CSi(CH₃)₂)₃CMgCH₃],

4.66 [sep, J=7 Hz, 3H, (C₆H₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CMgCH₃],

7.01-7.19 [m, 9H, (C₆ H ₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CMgCH₃],

8.83 [d, J=8 Hz, 3H, (C₆ H ₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CMgCH₃].

¹³C{¹H} NMR (C₆D₆):

0.57 [s, 1C, (C₆H₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CMgCH₃],

4.54 [s, 6C, (C₆H₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CMgCH₃],

21.01 [s, 6C, (C₆H₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CMgCH₃],

50.09 [s, 3C, (C₆H₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CMgCH₃],

112.24 [s, 3C, (C₆H₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CMgCH₃],

122.54 [s, 3C, (C₆H₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CMgCH₃],

122.69 [s, 3C, (C₆H₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CMgCH₃],

122.90 [s, 3C, (C₆H₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CMgCH₃],

134.55 [s, 3C, (C₆H₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CMgCH₃],

144.78 [s, 3C, (C₆H₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CMgCH₃],

166.94 [s, 3C, (C₆H₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CMgCH₃],

not observed [(C₆H₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CMgCH₃].

²⁹Si NMR (C₆D₆): −12.69 [s, 3Si, (C₆H₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CMgCH₃].

Anal. calc. for [Tism^(Pr) ^(i) ^(Benz)]MgMe.C₆H₆: C, 67.6%; H, 7.7%; N,10.8%. Found: C, 66.8%; H, 7.6%; N, 10.4%.

IR Data (ATR, cm⁻¹): 2973 (m), 1462 (m), 1391 (w), 1340 (m), 1257 (m),1060 (m), 1011 (m), 948 (s), 821 (vs), 739 (vs), 676 (s).

Preparation of [κ³-Tism^(Pr) ^(i) ^(Benz)]ZnMe

A solution of [Tism^(Pr) ^(i) ^(Benz)]H (30 mg, 0.045 mmol) in benzene(ca. 0.7 mL) was treated with Me₂Zn (15 mg, 0.157 mmol) in an NMR tubeequipped with a J. Young valve and the solution was heated at 60° C. for1 day. After this period the mixture was filtered and the filtrate waslyophilized to afford [κ³-Tism^(Pr) ^(i) ^(Benz)]ZnMe as a white powder(18 mg, 54%). Colorless crystals of [κ³-Tism^(Pr) ^(i) ^(Benz)]ZnMesuitable for X-ray diffraction were obtained by vapor diffusion ofpentane into a solution in benzene.

¹H NMR (C₆D₆):

0.31 [5, 3H, (C₆H₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CZnCH ₃],

0.76 [5, 18H, (C₆H₄N₂CH(CH₃)₂CSi(CH ₃)₂)₃CZnCH₃],

1.14 [d, J=6.9 Hz, 18H, (C₆H₄N₂CH(CH ₃)₂CSi(CH₃)₂)₃CZnCH₃],

4.70 [sept, J=7 Hz, 3H (C₆H₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CZnCH₃],

7.05 [m, 3H, (C₆ H ₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CZnCH₃],

7.23 [d, J=8.2 Hz, (C₆ H ₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CZnCH₃],

8.22 [d, J=8 Hz, (C₆ H ₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CZnCH₃].

¹³C NMR (C₆D₆):

−10.51 [s, 1C, (C₆H₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CZnCH₃],

4.98 [s, 6C, (C₆H₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CZnCH₃],

21.15 [s, 6C, (C₆H₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CZnCH₃],

49.97 [s, 3C, (C₆H₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CZnCH₃],

112.92 [s, 3C, (C₆H₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CZnCH₃],

119.85 [s, 3C, (C₆H₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CZnCH₃],

122.38 [s, 3C, (C₆H₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CZnCH₃],

122.50 [s, 3C, (C₆H₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CZnCH₃],

134.68 [s, 3C, (C₆H₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CZnCH₃],

144.59 [s, 3C, (C₆H₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CZnCH₃],

166.41 [s, 3C, (C₆H₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CZnCH₃],

not observed [(C₆H₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CZnCH₃].

²⁹Si NMR (C₆D₆): −7.97 [s, (C₆H₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CZnCH₃].

Anal. calc. for [k³-Tism^(Pr) ^(i) ^(Benz)]ZnMe: C, 61.3%; H, 7.3%; N,11.3%. Found: C, 61.7%; H, 6.7%; N, 10.2%.

IR Data (cm⁻¹): 2969 (w), 2896 (w), 1464 (m), 1390 (m), 1371 (m), 1354(m), 1290 (w), 1252 (m), 1132 (w), 1066 (m), 919 (s), 890 (s), 813 (s),739 (vs), 698 (m), 645 (m).

Preparation of [Tism^(Pr) ^(i) ^(Benz)]Cu

A solution of [(Me₃P)CuCl]₄ (16 mg, 0.023 mmol) in benzene (ca. 1.5 mL)was treated with [Tism^(Pr) ^(i) ^(Benz)]Li (50 mg, 0.075 mmol), therebyresulting in the formation of a yellow suspension. The suspension wasstirred for one day, after which period, the solvent was removed invacuo. The solid was washed with benzene (2×0.5 mL), resulting in[Tism^(Pr) ^(i) ^(Benz)]Cu as a yellow solid (16 mg, 30%). Yellowcrystals suitable for X-ray diffraction were obtained by vapor diffusionof pentane into a solution in benzene.

¹H NMR (C₆D₆):

0.58 [s, 18H, (C₆H₄N₂CH(CH₃)₂CSi(CH ₃)₂)₃CCu],

1.23 [d, J=7 Hz, 18H, (C₆H₄N₂CH(CH ₃)2CSi(CH₃)₂)₃CCu],

4.77 [sept, J=7 Hz, 3H, (C₆H₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CCu],

7.02 [m, 3H, (C₆ H ₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CCu],

7.11 [m, 3H, (C₆ H ₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CCu],

7.26 [d, J=8.1 Hz, 3H, (C₆ H ₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CCu],

8.29 [d, J=8 Hz, 3H, (C₆ H ₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CCu].

¹³C NMR (C₆D₆):

5.65 (6C, (C₆H₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CCu],

21.24 [6C, (C₆H₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CCu],

49.64 [3C, (C₆H₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CCu],

112.64 [3C, (C₆H₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CCu],

120.21 [3C, (C₆H₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CCu],

121.91 [3C, (C₆H₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CCu],

122.02 [3C, (C₆H₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CCu],

134.13 [3C, (C₆H₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CCu],

144.34 [3C, (C₆H₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CCu],

168.12 [3C, (C₆H₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CCu],

not observed [(C₆H₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CCu].

²⁹Si NMR (C₆D₆): −14.90 [s, 3Si, (C₆H₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CCu].

Anal. calc. for [Tism^(Pr) ^(i) ^(Benz)]Cu: C, 61.1%; H, 7.1%; N, 11.6%.Found: C, 60.8%; H, 7.0%; N, 11.4%.

IR Data (cm⁻¹): 3053 (w), 2963 (w), 1463 (m), 1389 (w), 1372 (w), 1344(m), 1321 (w), 1286 (w), 1249 (m), 1159 (w), 1133 (w), 1105 (m), 954(vs), 822 (s), 791 (s), 738 (vs), 669 (m).

Preparation of [Tism^(Pr) ^(i) ^(Benz)]NiBr

A mixture of [Tism^(Pr) ^(i) ^(Benz)]Li (50 mg, 0.075 mmol) and(Ph₃P)₂NiBr₂ (55 mg, 0.074 mmol) was dissolved in THF (ca. 2 mL) and thegreen solution obtained was allowed to stand over a period of 2 days,during which period green crystals of [Tism^(Pr) ^(i) ^(Benz)]NiBrsuitable for X-ray diffraction were deposited. The crystals wereisolated by decanting the mother liquor, washed sequentially with THF(ca. 1 mL) and pentane (ca. 1 mL), and dried in vacuo to afford[Tism^(Pr) ^(i) ^(Benz)]NiBr (37 mg, 61%).

¹H NMR (C₆D₆): 1.53 [bs], 4.85 [bs], 5.59 [bs], 8.09 [bs], 10.21 [bs],22.52 [bs], 29.88 [bs].

Anal. calc. for [Tism^(Pr) ^(i) ^(Benz)]NiBr: C, 55.4%; H, 6.4%; N,10.5%. Found: C, 54.1%; H, 6.6%; N, 9.1%.

IR Data (cm⁻¹): 2972 (w), 2943 (w), 2877 (w), 1466 (m) 1392 (m), 1363(m), 1252 (m), 1158 (w), 1133 (w), 1068 (m), 933 (s), 896 (s), 829 (s),815 (s), 766 (m), 737 (vs), 695 (m).

Preparation of [Tism^(Pr) ^(i) ^(Benz)]MgF

Two preparation methods were employed:

(i) A solution of [Tism^(Pr) ^(i) ^(Benz)]MgMe (10 mg, 0.014 mmol) inTHF (ca 0.7 mL) was treated with Me₃SnF (2 mg, 0.011 mmol). The solutionwas stirred at room temperature for 10 minutes, over which period all ofthe Me₃SnF dissolves. After this period, the solution was allowed tostand at room temperature for 16 hours, resulting in the deposition ofcolorless crystals of [Tism^(Pr) ^(i) ^(Benz)]MgF suitable for X-raydiffraction, which were washed with benzene and dried in vacuo (6 mg,60% yield).

(ii) A solution of [Tism^(Pr) ^(i) ^(Benz)]MgH (3 mg, 0.004 mmol) inbenzene (ca 0.7 mL) was treated with Me₃SnF (2 mg, 0.011 mmol) resultingin the formation of a white suspension. The reaction was monitored by ¹Hand ¹⁹F NMR spectroscopy, thereby demonstrating the immediate formationof [Tism^(Pr) ^(i) ^(Benz)]MgF and Me₃SnH.

Anal. calcd. for [Tism^(Pr) ^(i) ^(Benz)]MgF.C₄H₈O: C, 63.2%; H, 7.6%;N, 10.8%. Found: C, 63.0%; H, 7.5%; N, 10.2%.

¹H NMR (C₆D₆):

0.40 [s, 18H, (C₆H₄N₂CH(CH₃)₂CSi(CH ₃)₂)₃CMgF],

1.20 [d, J=7 Hz, 18H, (C₆H₄N₂CH(CH ₃)₂CSi(CH₃)₂)₃CMgF],

4.67 [sep, J=7 Hz, 3H, (C₆H₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CMgF],

7.04 [t, J=7 Hz, 3H, (C₆ H ₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CMgF],

7.19 [d, J=7 Hz, 3H, (C₆ H ₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CMgF],

7.22 [t, J=7 Hz, 3H, (C₆ H ₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CMgF],

9.97 [dd, J=8 Hz, J=3 Hz, 3H, (C₆ H ₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CMgF].

¹³C{¹H} NMR (C₆D₆):

4.85 [s, 6C, (C₆H₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CMgF],

21.14 [s, 6C, (C₆H₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CMgF],

50.03 [s, 3C, (C₆H₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CMgF],

111.79 [s, 3C, (C₆H₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CMgF],

122.97 [s, 3C, (C₆H₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CMgF],

123.06 [s, 3C, (C₆H₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CMgF],

124.07 [d, J=15 Hz, 3C, (C₆H₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CMgF],

134.02[s, 3C, (C₆H₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CMgF],

145.14 [s, 3C, (C₆H₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CMgF],

167.53 [s, 3C, (C₆H₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CMgF],

not observed [(C₆H₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CMgF].

²⁹Si NMR (C₆D₆): −12.18 [s, 3Si, (C₆H₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CMgF].

¹⁹F NMR (C₆D₆): −152.4 [s, 1F, (C₆H₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CMgF].

IR Data (ATR, cm⁻¹): 1356 (m), 943 (vs), 825 (s), 790 (s), 742 (vs), 697(m), 675 (m), 530 (m), 497 (m), 436 (m).

Preparation of [Tism^(Pr) ^(i) ^(Benz)]MgCl

Two preparation methods were employed:

(i) A solution of [Tism^(Pr) ^(i) ^(Benz)]MgMe (30 mg, 0.043 mmol) inC₆D₆ (ca 0.7 mL) was treated with Me₃SnCl (10 mg, 0.050 mmol). Themixture was filtered after 10 minutes and the filtrate was lyophilizedto afford [Tism^(Pr) ^(i) ^(Benz)]MgCl as a white powder (23 mg, 74%yield). Colorless crystals suitable for X-ray diffraction were obtainedvia vapor diffusion of pentane into a concentrated benzene solution.

(ii) A solution of [Tism^(Pr) ^(i) ^(Benz)]MgH (2 mg, 0.003 mmol) inC₆D₆ (ca 0.7 mL) was treated with Me₃SnCl. The reaction was monitored by¹H NMR spectroscopy, thereby demonstrating the immediate formation of[Tism^(Pr) ^(i) ^(Benz)]MgCl and Me₃SnH.

¹H NMR (C₆D₆):

0.36 [s, 18H, (C₆H₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CMgCl],

1.13 [d, J=7 Hz, 18H, (C₆H₄N₂CH(CH ₃)₂CSi(CH₃)₂)₃CMgCl],

4.59 [sep, J=7 Hz, 3H, (C₆H₄N₂CH(CH ₃)₂CSi(CH₃)₂)₃CMgCl],

7.02 [t, J=7 Hz, 3H, (C₆ H ₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CMgCl],

7.13 [m, 6H, (C₆ H ₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CMgCl],

9.92 [d, J=8 Hz, 3H, (C₆ H ₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CMgCl].

¹³C{¹H} NMR (C₆D₆):

4.25 [s, 6C, (C₆H₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CMgCl],

20.97 [s, 6C, (C₆H₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CMgCl],

50.21 [s, 3C, (C₆H₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CMgCl],

111.92 [s, 3C, (C₆H₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CMgCl],

122.80 [s, 3C, (C₆H₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CMgCl],

123.02 [s, 3C, (C₆H₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CMgCl],

124.53 [s, 3C, (C₆H₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CMgCl],

134.32 [s, 3C, (C₆H₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CMgCl],

144.69 [s, 3C, (C₆H₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CMgCl],

166.83 [s, 3C, (C₆H₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CMgCl],

not observed [(C₆H₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CMgCl].

²⁹Si NMR (C₆D₆): −12.19 [s, 3Si, (C₆H₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CMgCl].

IR Data (ATR, cm⁻¹): 1358 (m), 939 (s), 826 (s), 814 (s), 790 (m), 741(vs), 695 (m), 559 (m), 531 (m), 440 (m).

Preparation of [Tism^(Pr) ^(i) ^(Benz)]MgBr

Two preparation methods were employed:

(i) A solution of [Tism^(Pr) ^(i) ^(Benz)]MgMe (30 mg, 0.043 mmol) inC₆D₆ (ca 0.7 mL) was treated with Me₃SnBr (12 mg, 0.049 mmol). After 10minutes, the solution was filtered and lyophilized to afford [Tism^(Pr)^(i) ^(Benz)]MgBr as a white powder (26 mg, 79% yield). Colorlesscrystals suitable for X-ray diffraction were obtained via vapordiffusion of pentane into a concentrated toluene solution.

(ii) A solution of [Tism^(Pr) ^(i) ^(Benz)]MgH (2 mg, 0.003 mmol) inC₆D₆ (ca 0.7 mL) was treated with Me₃SnBr. The reaction was monitored by¹H NMR spectroscopy, thereby demonstrating the immediate formation of[Tism^(Pr) ^(i) ^(Benz)]MgBr and Me₃SnH. Anal. calcd. for [Tism^(Pr)^(i) ^(Benz)]MgBr: C, 57.8%; H, 6.7%; N, 10.9%. Found: C, 56.2%; H,6.9%; N, 10.3%.

¹H NMR (C₆D₆):

0.35 [s, 18H, (C₆H₄N₂CH(CH₃)₂CSi(CH ₃)₂)₃CMgBr],

1.12 [d, J=7 Hz, 18H, (C₆H₄N₂CH(CH ₃)₂CSi(CH₃)₂)₃CMgBr],

4.57 [sep, J=7 Hz, 3H, (C₆H₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CMgBr],

7.01 [t, J=7 Hz, 3H, (C₆ H ₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CMgBr],

7.10 [t, J=7 Hz, 3H, (C₆ H ₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CMgBr],

7.14 [d, J=8 Hz, 3H, (C₆ H ₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CMgBr],

9.94 [d, J=8 Hz, 3H, (C₆ H ₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CMgBr].

¹³C{¹H} NMR (C₆D₆):

4.13 [s, 6C, (C₆H₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CMgBr],

20.94 [s, 6C, (C₆H₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CMgBr],

50.28 [s, 3C, (C₆H₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CMgBr],

111.94 [s, 3C, (C₆H₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CMgBr],

122.64 [s, 3C, (C₆H₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CMgBr],

123.08 [s, 3C, (C₆H₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CMgBr],

124.79 [s, 3C, (C₆H₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CMgBr],

134.42 [s, 3C, (C₆H₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CMgBr],

144.48 [s, 3C, (C₆H₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CMgBr],

166.63 [s, 3C, (C₆H₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CMgBr],

not observed [(C₆H₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CMgBr].

²⁹Si NMR (C₆D₆): −12.13 [s, 3Si, (C₆H₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CMgBr].

IR Data (ATR, cm⁻¹): 1358 (w), 939 (m), 826 (m), 813 (m), 790 (w), 741(s), 695 (w), 560 (w), 531 (w), 442 (w).

Preparation of [Tism^(Pr) ^(i) ^(Benz)]MgI

Two Preparation Methods were Employed:

(i) A solution of [Tism^(Pr) ^(i) ^(Benz)]MgMe (30 mg, 0.043 mmol) inC₆D₆ (ca 0.7 mL) was treated with a solution of Me₃SnI (ca 1 equiv inC₆D₆). The solution was filtered after 10 minutes, and lyophilized toafford [Tism^(Pr) ^(i) ^(Benz)]MgI as a white powder (25 mg, 72% yield).Colorless crystals suitable for X-ray diffraction were obtained viavapor diffusion of pentane into a concentrated benzene solution.

(ii) A solution of [Tism^(Pr) ^(i) ^(Benz)]MgH (2 mg, 0.003 mmol) inC₆D₆ (ca 0.7 mL) was treated with Me₃SnI (ca. 1 equiv in C₆D₆). Thereaction was monitored by 1H NMR spectroscopy, thereby demonstrating theimmediate formation of [Tism^(Pr) ^(i) ^(Benz)]MgI and Me₃SnH.

¹H NMR (C₆D₆):

0.34 [s, 18H, (C₆H₄N₂CH(CH₃)₂CSi(CH3)₂)₃CMgI],

1.10 [d, J=7 Hz, 18H, (C₆H₄N₂CH(CH ₃)₂CSi(CH₃)₂)₃CMgI],

4.55 [sep, J=7 Hz, 3H, (C₆H₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CMgI],

6.99 [t, J=7 Hz, 3H, (C₆ H ₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CMgI],

7.11 [m, 6H, (C₆ H ₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CMgI],

9.86 [d, J=8 Hz, 3H, (C₆H₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CMgI].

¹³C{¹H} NMR (C₆D₆):

4.21 [s, 6C, (C₆H₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CMgI],

20.92 [s, 6C, (C₆H₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CMgI],

50.34 [s, 3C, (C₆H₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CMgI],

112.04 [s, 3C, (C₆H₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CMgI],

122.33 [s, 3C, (C₆H₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CMgI],

123.15 [s, 3C, (C₆H₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CMgI],

124.97 [s, 3C, (C₆H₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CMgI],

134.53 [s, 3C, (C₆H₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CMgI],

144.05 [s, 3C, (C₆H₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CMgI],

166.32 [s, 3C, (C₆H₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CMgI],

not observed [(C₆H₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CMgI].

²⁹Si NMR (C₆D₆): −11.81 [s, 3Si, (C₆H₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CMgI].

IR Data (ATR, cm⁻¹): 1358 (w), 939 (s), 825 (vs), 791 (m), 741 (vs), 695(m), 650 (m), 634 (m), 560 (m), 530 (m), 443 (m).

Preparation of [Tism^(Pr) ^(i) ^(Benz)]MgSH

Two preparation methods were employed:

(i) A solution of [Tism^(Pr) ^(i) ^(Benz)]MgMe (10 mg, 0.014 mmol) inC₆D₆ (ca 0.7 mL) was treated with H₂S (1 atm). Excess H₂S was removed bya freeze-pump-thaw cycle, after which, the mixture was filtered. Thefiltrate was lyophilized to afford [Tism^(Pr) ^(i) ^(Benz)]MgSH as awhite powder (7 mg, 68% yield). Colorless crystals suitable for X-raydiffraction were obtained via vapor diffusion of pentane into aconcentrated benzene solution.

(ii) A solution of [Tism^(Pr) ^(i) ^(Benz)]MgH (5 mg, 0.007 mmol) inC₆D₆ (ca 0.7 mL) was treated with H₂S (1 atm), resulting in a colorchange from light yellow to colorless. The formation of [Tism^(Pr) ^(i)^(Benz)]MgSH was confirmed by ¹H NMR spectroscopy.

¹H NMR (C₆D₆):

−1.07 [s, 1H, (C₆H₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CMgSH],

0.38 [s, 18H, (C₆H₄N₂CH(CH₃)₂CSi(CH ₃)₂)₃CMgSH],

1.13 [d, J=7 Hz, 18H, (C₆H₄N₂CH(CH ₃)₂CSi(CH₃)₂)₃CMgSH],

7.00 [t, J=7 Hz, 3H, (C₆ H ₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CMgSH],

7.08 [t, J=7 Hz, 3H, (C₆ H ₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CMgSH],

7.14 [d, J=2 Hz, 3H, (C₆ H ₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CMgSH],

9.65 [d, J=8 Hz, 3H, (C₆ H ₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CMgSH].

¹³C{¹H} NMR (C₆D₆):

4.32 [s, 6C, (C₆H₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CMgSH],

20.96 [s, 6C, (C₆H₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CMgSH],

50.22 [s, 3C, (C₆H₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CMgSH],

112.06 [s, 3C, (C₆H₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CMgSH],

122.64 [s, 3C, (C₆H₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CMgSH],

123.00 [s, 3C, (C₆H₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CMgSH],

124.11 [s, 3C, (C₆H₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CMgSH],

134.44 [s, 3C, (C₆H₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CMgSH],

144.52 [s, 3C, (C₆H₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CMgSH],

166.61 [s, 3C, (C₆H₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CMgSH],

not observed [(C₆H₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CMgSH].

²⁹Si NMR (C₆D₆): −12.17 [s, 3Si, (C₆H₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CMgSH].

IR Data (ATR, cm⁻¹): 1358 (w), 1254 (w), 1064 (w), 942 (m), 826 (s), 790(m), 741 (vs), 695 (w), 675 (w), 438 (m).

Preparation of [Tism^(Pr) ^(i) ^(Benz)]MgN(H)Ph

Two preparation methods were employed:

(i) A solution of [Tism^(Pr) ^(i) ^(Benz)]MgMe (15 mg, 0.021 mmol) inC₆D₆ (ca 0.7 mL) was treated with aniline (2.0 mg, 0.021 mmol). Thesolution was filtered after 10 minutes and the filtrate was lyophilizedto afford [Tism^(Pr) ^(i) ^(Benz)]MgN(H)Ph (13 mg, 79% yield). Goldcrystals suitable for X-ray diffraction were obtained via vapordiffusion of pentane into a concentrated benzene solution.

(ii) A solution of [Tism^(Pr) ^(i) ^(Benz)]MgH (3 mg, 0.004 mmol) inC₆D₆ (ca 0.7 mL) was treated with aniline (0.5 mg, 0.005 mmol). Thesolution changed from light yellow to colorless and the formation of[Tism^(Pr) ^(i) ^(Benz)]MgN(H)Ph was confirmed by ¹H NMR spectroscopy.

Anal. calcd. for [Tism^(Pr) ^(i) ^(Benz)]MgN(H)Ph: C, 66.2%; H, 7.4%; N,12.6%. Found: C, 65.5%; H, 7.6%; N, 12.3%.

¹H NMR (C₆D₆):

0.41 [s, 18H, (C₆H₄N₂CH(CH ₃)₂CSi(CH₃)₂)₃CMgN(H)Ph],

1.18 [d, J=7 Hz, 18H, (C₆H₄N₂CH(CH ₃)₂CSi(CH₃)₂)₃CMgN(H)Ph],

4.44 [s, 1H, (C₆H₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CMgN(H)Ph],

4.66 [sep, J=7 Hz, 3H, (C₆H₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CMgN(H)Ph],

6.31 [t, J=7 Hz, 1H, (C₆H₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CMgN(H)Ph],

6.61 [d, J=7 Hz, 2H, (C₆H₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CMgN(H)Ph],

6.98 [m, 8H, (C₆ H ₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CMgN(H)Ph],

7.14 [d, J=8 Hz, 3H, (C₆ H ₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CMgN(H)Ph],

8.86 [d, J=8 Hz, 3H, (C₆ H ₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CMgN(H)Ph].

¹³C{¹H} NMR (C₆D₆):

4.57 [s, 6C, (C₆H₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CMgN(H)Ph],

21.05 [s, 6C, (C₆H₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CMgN(H)Ph],

50.20 [s, 3C, (C₆H₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CMgN(H)Ph],

108.99 [s, 1C, (C₆H₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CMgN(H)Ph],

112.05 [s, 3C, (C₆H₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CMgN(H)Ph],

116.99 [s, 2C, (C₆H₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CMgN(H)Ph],

122.74 [s, 1C, (C₆H₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CMgN(H)Ph],

122.96 [s, 3C, (C₆H₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CMgN(H)Ph],

123.07 [s, 3C, (C₆H₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CMgN(H)Ph],

129.13 [s, 2C, (C₆H₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CMgN(H)Ph],

134.20 [s, 3C, (C₆H₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CMgN(H)Ph],

144.19 [s, 3C, (C₆H₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CMgN(H)Ph],

161.85 [s, 1C, (C₆H₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CMgN(H)Ph],

167.09 [s, 3C, (C₆H₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CMgN(H)Ph],

not observed [(C₆H₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CMgN(H)Ph].

²⁹Si NMR (C₆D₆): −12.13 [s, 3Si, (C₆F₁₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CMgN(H)Ph].

IR Data (ATR, cm⁻¹): 2917 (w), 2849 (w), 1603 (w), 1524 (m), 1499 (w),1462 (m), 1397 (w), 1340 (w), 1266 (w), 1133 (w), 1061 (w), 1011 (w),948 (w), 821 (s), 741 (vs), 692 (m), 505 (m), 431 (m).

Preparation of [Tism^(Pr) ^(i) ^(Benz)]Mg(κ²-O₂CMe)

A solution of [Tism^(Pr) ^(i) ^(Benz)]MgMe (30 mg, 0.043 mmol) in C₆D₆(ca 0.7 mL) was treated with CO₂ (1 atm). The solution immediatelyturned cloudy. After one hour, the precipitate was collected and washedwith benzene to afford [Tism^(Pr) ^(i) ^(Benz)]Mg (κ²-O₂CMe) as a whitepowder (22 mg, 69% yield). Colorless crystals suitable for X-raydiffraction were obtained via vapor diffusion of pentane into aconcentrated solution of toluene.

Anal. calcd. for [Tism^(Pr) ^(i) ^(Benz)]Mg(k²_O₂CMe): C, 62.7%; H,7.3%; N, 11.3%. Found: C, 63.2%; H, 6.6%; N, 10.5%.

¹H NMR (C₆D₆):

0.72 [s, 18H, (C₆H₄N₂CH(CH ₃)₂CSi(CH₃)₂)₃CMgOC(O)CH₃],

1.08 [d, J=7 Hz, 18H, (C₆H₄N₂CH(CH ₃)₂CSi(CH₃)₂)₃CMgOC(O)CH₃],

2.04 [s, 3H, (C₆H₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CMgOC(O)CH ₃],

4.68 [sep, J=7 Hz, 3H, (C₆H₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CMgOC(O)CH₃],

6.94 [t, J=7 Hz, 3H, (C₆ H ₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CMgOC(O)CH₃],

7.06 [d, J=8 Hz, 3H, (C₆ H ₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CMgOC(O)CH₃],

7.22 [t, J=7 Hz, 3H, (C₆ H ₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CMgOC(O)CH₃],

9.15 [d, J=8 Hz, 3H, (C₆ H ₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CMgOC(O)CH₃].

¹³C{¹H} NMR (C₆D₆):

6.95 [s, 6C, (C₆H₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CMgOC(O)CH₃],

20.97 [s, 6C, (C₆H₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CMgOC(O)CH₃],

23.42 [s, 1C, (C₆H₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CMgOC(O)CH₃],

49.59 [s, 3C, (C₆H₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CMgOC(O)CH₃],

112.47 [s, 3C, (C₆H₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CMgOC(O)CH₃],

121.52 [s, 3C, (C₆H₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CMgOC(O)CH₃],

122.34 [s, 3C, (C₆H₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CMgOC(O)CH₃],

122.39 [s, 3C, (C₆H₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CMgOC(O)CH₃],

134.15 [s, 3C, (C₆H₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CMgOC(O)CH₃],

144.19 [s, 3C, (C₆H₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CMgOC(O)CH₃],

165.91 [s, 3C, (C₆H₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CMgOC(O)CH₃],

183.12 [s, 1C, (C₆H₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CMgOC(O)CH₃],

not observed [(C₆H₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CMgOC(O)CH₃].

²⁹Si NMR (C₆D₆): −10.37 [s, 3Si, (C₆H₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CMgOC(O)CH₃].

IR Data (ATR, cm⁻¹): 3056 (w), 3000 (w), 2974 (w), 2942 (w), 2896 (w),1534 (m), 1464 (m), 1356 (m), 940 (s), 906 (s), 828 (m), 816 (m), 795(m), 741 (s), 684 (m), 675 (m), 506 (m).

Preparation of [Tism^(Pr) ^(i) ^(Benz)]Mg(κ²-S₂CMe)

A solution of [Tism^(Pr) ^(i) ^(Benz)]MgMe (30 mg, 0.043 mmol) in C₆D₆(ca 0.7 mL) was treated with CS₂ (4 mg, 0.053 mmol). The solutionimmediately turned yellow. The solution was allowed to stand for aperiod of four days, after which time the precipitate was collected andwashed with benzene to afford [Tism^(Pr) ^(i) ^(Benz)]Mg (κ²-S₂CMe) as ayellow powder (20 mg, 60% yield). Colorless crystals suitable for X-raydiffraction were obtained from a solution in benzene.

¹H NMR (C₆D₆):

0.58 [s, 18H, (C₆H₄N₂CH(CH₃)₂CSi(CH ₃)₂)₃CMgSC(S)CH₃],

1.16 [d, J=7 Hz, 18H, (C₆H₄N₂CH(CH ₃)₂CSi(CH₃)₂)₃CMgSC(S)CH₃],

2.89 [s, 3H, (C₆H₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CMgSC(S)CH ₃],

4.67 [sep, J=7 Hz, 3H, (C₆H₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CMgSC(S)CH₃],

6.96 [t, J=7 Hz, 3H, (C₆ H ₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CMgSC(S)CH₃],

7.13 [m, 6H, (C₆ H ₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CMgSC(S)CH₃],

9.03 [d, J=8 Hz, 3H, (C₆ H ₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CMgSC(S)CH₃].

¹H NMR (C₇D₈):

0.52 [s, 18H, (C₆H₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CMgSC(S)CH₃],

1.21 [d, J=7 Hz, 18H, (C₆H₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CMgSC(S)CH₃],

2.78 [s, 3H, (C₆H₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CMgSC(S)CH ₃],

4.68 [sep, J=7 Hz, 3H, (C₆H₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CMgSC(S)CH₃],

6.95 [t, J=7 Hz, 3H, (C₆ H ₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CMgSC(S)CH₃],

7.08 [m, 3H, (C₆ H ₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CMgSC(S)CH₃],

7.12 [d, J=8 Hz, 3H, (C₆ H ₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CMgSC(S)CH₃],

8.85 [d, J=8 Hz, 3H, (C₆ H ₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CMgSC(S)CH₃].

¹³C{¹H} NMR (C₇D₈):

5.77 [s, 6C, (C₆H₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CMgSC(S)CH₃],

20.99 [s, 6C, (C₆H₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CMgSC(S)CH₃],

45.75 [s, 1C, (C₆H₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CMgSC(S)CH₃],

50.02 [s, 3C, (C₆H₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CMgSC(S)CH₃],

112.24 [s, 3C, (C₆H₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CMgSC(S)CH₃],

122.15 [s, 3C, (C₆H₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CMgSC(S)CH₃],

122.37 [s, 3C, (C₆H₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CMgSC(S)CH₃],

122.54 [s, 3C, (C₆H₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CMgSC(S)CH₃],

134.29 [s, 3C, (C₆H₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CMgSC(S)CH₃],

144.10 [s, 3C, (C₆H₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CMgSC(S)CH₃],

166.63 [s, 3C, (C₆H₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CMgSC(S)CH₃],

not observed [s, 1C, (C₆H₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CMgSC(S)CH₃],

not observed [(C₆H₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CMgSC(S)CH₃].

²⁹Si NMR (C₇D₈): −11.37 [s, 3Si, (C₆H₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CMgSC(S)CH₃].

IR Data (ATR, cm⁻¹): 3051 (w), 2972 (w), 2939 (w), 2892 (w), 1462 (w),1391 (w), 1372 (w), 1353 (w), 1151(w), 1133 (w), 1065 (w), 926 (s), 891(s), 846 (w), 826 (m), 812 (m), 793 (s), 760 (w), 737 (s), 695 (w), 679(w), 502 (w), 488 (w), 439 (w).

Preparation of [Tism^(Pr) ^(i) ^(Benz)]MgH

A solution of PhSiH₃ (9 μL, 0.073 mmol) in C₆D₆ (ca 0.7 mL) was added to[Tism^(Pr) ^(i) ^(Benz)]MgMe (30 mg, 0.043 mmol) in an NMR tube equippedwith a J. Young tube. The solution was allowed to stand at roomtemperature for 16 hours and then filtered. The filtrate was lyophilizedto afford [Tism^(Pr) ^(i) ^(Benz)]MgH as an off-white powder (20 mg, 68%yield). Colorless crystals suitable for X-ray diffraction were obtaineddirectly from the benzene filtrate of the reaction mixture.

¹H NMR (C₆D₆):

0.43 [s, 18H, (C₆H₄N₂CH(CH₃)₂CSi(CH ₃)₂)₃CMgH],

1.18 [d, J=7 Hz, 18H, (C₆H₄N₂CH(CH ₃)₂CSi(CH₃)₂)₃CMgH],

4.68 [sep, J=7 Hz, 3H, (C₆H₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CMgH],

6.78 [s, 1H, (C₆H₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CMgH],

7.03 [t, J=7 Hz, 3H, (C₆ H ₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CMgH],

7.18 [m, 6H, (C₆ H ₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CMgH],

9.89 [d, J=8 Hz, 3H, (C₆ H ₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CMgH].

¹³C{¹H} NMR (C₆D₆):

4.80 [s, 6C, (C₆H₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CMgH],

21.11 [s, 6C, (C₆H₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CMgH],

50.04 [s, 3C, (C₆H₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CMgH],

112.03 [s, 3C, (C₆H₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CMgH],

122.49 [s, 3C, (C₆H₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CMgH],

122.76 [s, 3C, (C₆H₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CMgH],

123.52 [s, 3C, (C₆H₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CMgH],

134.31 [s, 3C, (C₆H₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CMgH],

145.22 [s, 3C, (C₆H₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CMgH],

167.17 [s, 3C, (C₆H₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CMgH],

not observed [(C₆H₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CMgH].

²⁹Si NMR (C₆D₆): −12.49 [s, 3Si, (C₆H₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CMgH].

IR Data (FT-IR, cm⁻¹): 3057 (w), 2974 (m), 2941 (m), 2894 (w), 1465 (m),1391 (w), 1371 (w), 1356 (m), 1323 (w), 1302 (w), 1282 (w), 1252 (m),1066 (m) 1012 (w), 949 (s), 827 (s), 790 (m), 746 (s).

Preparation of [Tism^(Pr) ^(i) ^(Benz)]MgCH(Me)Ph

Three preparation methods were employed:

(i) A solution of [Tism^(Pr) ^(i) ^(Benz)]MgMe (30 mg, 0.043 mmol) inC₆D₆ (ca. 0.7 mL) was treated with PhSiH₃ and styrene (ca 1.5equivalents each). The mixture was allowed to stand at room temperaturefor 16 hours, after which period, the mixture was lyophilized to afforda yellow powder. The solid obtained was washed with benzene (1×1 mL) andpentane (1×1 mL) to afford [Tism^(Pr) ^(i) ^(Benz)]MgCH(Me)Ph (17 mg,50%) as an off-white powder. Colorless crystals suitable for X-raydiffraction were formed by slowly cooling a saturated solution from 60°C. to room temperature.

(ii) A solution of [Tism^(Pr) ^(i) ^(Benz)]MgH (10 mg, 0.015 mmol) inbenzene (ca 0.7 mL) was treated with styrene (2 mg, 0.019 mmol), andstirred for 2 hours at room temperature. After this period, the mixturewas lyophilized and the solid was washed with benzene to afford[Tism^(Pr) ^(i) ^(Benz)]MgCH(Me)Ph as a white powder.

(iii) A solution of [Tism^(Pr) ^(i) ^(Benz)]MgH (2 mg, 0.003 mmol) inC₆D₆ (ca 0.7 mL) was treated with styrene (10 equivalents, 0.029 mmol).The reaction was monitored by ¹H NMR spectroscopy, thereby demonstratingcomplete consumption of [Tism^(Pr) ^(i) ^(Benz)]MgH after 10 minutes atroom temperature.

¹H NMR (C₆D₆):

0.56 [s, 9H, (C₆H₄N₂CH(CH₃)₂CSi(CH ₃)₂)₃CMgCH(Me)Ph],

0.59 [s, 9H, (C₆H₄N₂CH(CH₃)₂CSi(CH ₃)₂)₃CMgCH(Me)Ph],

1.04 [d, J=7 Hz, 9H, (C₆H₄N₂CH(CH ₃)₂CSi(CH₃)₂)₃CMgCH(Me)Ph],

1.09 [d, J=7 Hz, 9H, (C₆H₄N₂CH(CH ₃)₂CSi(CH₃)₂)₃CMgCH(Me)Ph],

2.03 [d, J=7 Hz, 3H, (C₆H₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CMgCH(Me)Ph],

2.64 [q, J=7 Hz, 1H, (C₆H₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CMgCH(Me)Ph],

4.58 [sep, J=7 Hz, 3H, (C₆H₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CMgCH(Me)Ph],

6.91 [t, 8 Hz, 1H, (C₆H₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CMgCH(Me)Ph],

6.92 [t, 8 Hz, 3H, (C₆ H ₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CMgCH(Me)Ph],

7.06 [d, 9 Hz, 3H, (C₆ H ₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CMgCH(Me)Ph],

7.11 [t, 8 Hz, 3H, (C₆ H ₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CMgCH(Me)Ph],

7.13 [d, 8 Hz, 2H, (C₆H₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CMgCH(Me)Ph],

7.30 [t, 8 Hz, 2H, (C₆H₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CMgCH(Me)Ph],

7.87 [d, J=8 Hz, 3H, (C₆ H ₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CMgCH(Me)Ph].

¹³C{¹H} NMR (C₆D₆):

6.52 [s, 3C, (C₆H₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CMgCH(Me)Ph],

6.76 [s, 3C, (C₆H₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CMgCH(Me)Ph],

19.84 [s, 1C, (C₆H₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CMgCH(Me)Ph],

20.89 [s, 3C, (C₆H₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CMgCH(Me)Ph],

21.07 [s, 3C, (C₆H₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CMgCH(Me)Ph],

33.87 [s, 1C, (C₆H₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CMgCH(Me)Ph],

49.65 [s, 3C, (C₆H₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CMgCH(Me)Ph],

112.46 [s, 3C, (C₆H₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CMgCH(Me)Ph],

115.51 [s, 1C, (C₆H₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CMgCH(Me)Ph],

120.98 [s, 3C, (C₆H₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CMgCH(Me)Ph],

122.30 [s, 3C, (C₆H₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CMgCH(Me)Ph],

122.58 [s, 3C, (C₆H₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CMgCH(Me)Ph],

123.16 [s, 2C, (C₆H₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CMgCH(Me)Ph],

133.78 [s, 3C, (C₆H₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CMgCH(Me)Ph],

143.73 [s, 3C, (C₆H₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CMgCH(Me)Ph],

162.35 [s, 1C, (C₆H₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CMgCH(Me)Ph],

165.12 [s, 3C, (C₆H₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CMgCH(Me)Ph],

not observed [(C₆H₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CMgCH(Me)Ph],

2C obscured by solvent [(C₆H₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CMgCH(Me)Ph].

²⁹Si NMR (C₆D₆): −10.31 [s, 3Si,(C₆F₁₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CMgCH(Me)Ph].

IR Data (ATR, cm⁻¹): 2973 (w), 1605 (w), 1460 (m), 1392 (w), 1370 (w),1339 (m), 1323 (w), 1266 (w), 1158 (w), 1132 (w), 1104 (w), 1060 (m),1010 (w), 948 (w), 820 (vs), 779 (s), 739 (vs), 696 (m), 649 (m), 540(m), 499 (m), 430 (m).

Preparation of [κ³-Tism^(Pr) ^(i) ^(Benz)]ZnBr

A mixture of ZnBr₂ (115 mg, 0.511 mmol) and [Tism^(Pr) ^(i) ^(Benz)]Li(300 mg, 0.447 mmol) in THF (ca 5 mL) was stirred for 30 minutes at roomtemperature. After this period, the volatile components were removed invacuo resulting in the formation of a sticky solid, which was treatedwith pentane (ca 5 mL). The mixture was stirred for 10 minutes and thevolatile components were removed in vacuo to afford an off-white powder.The solid was extracted into benzene (ca 10 mL) and lyophilized toafford [κ³-Tism^(Pr) ^(i) ^(Benz)]ZnBr (250 mg, 69%) as a white powder.Colorless crystals suitable for X-ray diffraction were obtained by thevapor diffusion of pentane into a concentrated solution in benzene.

Anal. calcd. for [k³-Tism^(Pr) ^(i) ^(Benz)]ZnBr.0.5C₆H₆: C, 56.6%; H,6.4%; N, 9.9%. Found: C, 56.5%; H, 6.2%; N, 9.2%.

¹H NMR (C₆D₆):

0.77 [s, 18H, (C₆H₄N₂CH(CH₃)₂CSi(CH ₃)₂)₃CZnBr],

1.12 [d, J=7 Hz, 18H, (C₆H₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CZnBr],

4.65 [sep, J=7 Hz, 3H, (C₆H₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CZnBr],

7.04 [m, 3H, (C₆ H ₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CZnBr],

7.17 [m, 6H, (C₆ H ₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CZnBr],

8.55 [d, J=8 Hz, 3H, (C₆ H ₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CZnBr].

¹³C{¹H} NMR (C₆D₆):

4.72 [s, 6C, (C₆H₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CZnBr],

21.09 [s, 6C, (C₆H₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CZnBr],

50.29 [s, 3C, (C₆H₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CZnBr],

112.94 [s, 3C, (C₆H₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CZnBr],

120.21 [s, 3C, (C₆H₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CZnBr],

122.82 [s, 3C, (C₆H₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CZnBr],

122.94 [s, 3C, (C₆H₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CZnBr],

134.58 [s, 3C, (C₆H₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CZnBr],

143.88 [s, 3C, (C₆H₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CZnBr],

165.99 [s, 3C, (C₆H₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CZnBr],

not observed [(C₆H₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CZnBr].

²⁹Si NMR (C₆D₆): −6.75 [s, 3Si, (C₆H₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CZnBr].

IR Data (ATR, cm⁻¹): 2974 (w), 1463 (w), 1390 (w), 1367 (w), 1323 (w),1293 (w), 1255 (w), 1068 (w), 881 (s), 830 (s), 814 (s), 798 (m), 766(w), 740 (s), 695 (w), 652 (w), 564 (w).

Preparation of [κ³-Tism^(Pr) ^(i) ^(Benz)]ZnH

A mixture of [Tism^(Pr) ^(i) ^(Benz)]Li (300 mg, 0.447 mmol) and ZnBr₂(111 mg, 0.493 mmol) in THF (ca 10 mL) was stirred for 30 minutes atroom temperature. After this period, the volatile components wereremoved in vacuo, resulting in the formation of a sticky solid, whichwas extracted into benzene (ca 10 mL) and then treated with KOSiMe₃(90%, 116 mg, 0.81 mmol). The mixture was stirred for 10 minutes and awhite precipitate was deposited. The mixture was filtered and thefiltrate was treated with PhSiH₃ (150 mg, 1.386 mmol) and the mixturewas stirred for 5 minutes. After this period, the volatile componentswere removed by lyophilization and the resulting light yellow solid waswashed with diethyl ether (1×2 mL). Colorless crystals of [κ³-Tism^(Pr)^(i) ^(Benz)]ZnH (110 mg, 34%) suitable for X-ray diffraction wereobtained from a solution in benzene.

Anal. calcd. for [k³-Tism^(Pr) ^(i) ^(Benz)]ZnH: C, 60.8%; H, 7.2%; N,11.5%. Found: C, 61.3%; H, 7.0%; N, 11.1%.

¹H NMR (C₆D₆):

0.81 [s, 18H, (C₆H₄N₂CH(CH₃)₂CSi(CH ₃)₂)₃CZnH],

1.14 [d, J=7 Hz, 18H, (C₆H₄N₂CH(CH ₃)₂CSi(CH₃)₂)₃CZnH],

4.72 [sep, J=7 Hz, 3H, (C₆H₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CZnH],

5.53 [s, 1H, (C₆H₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CZnH],

7.05 [m, 3H, (C₆ H ₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CZnH],

7.15 [m, 3H, (C₆ H ₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CZnH],

7.23 [d, J=9 Hz, 3H, (C₆ H ₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CZnH],

8.24 [d, J=8 Hz, 3H, (C₆ H ₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CZnH].

¹³C{¹H} NMR (C₆D₆):

5.03 [s, 6C, (C₆H₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CZnH],

21.17 [s, 6C, (C₆H₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CZnH],

50.04 [s, 3C, (C₆H₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CZnH],

112.88 [s, 3C, (C₆H₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CZnH],

119.96 [s, 3C, (C₆H₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CZnH],

122.41 [s, 3C, (C₆H₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CZnH],

122.54 [s, 3C, (C₆H₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CZnH],

134.58 [s, 3C, (C₆H₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CZnH],

144.53 [s, 3C, (C₆H₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CZnH],

166.62 [s, 3C, (C₆H₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CZnH],

not observed [(C₆H₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CZnH].

²⁹Si NMR (C₆D₆): −7.70 [s, 3Si, (C₆H₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CZnH].

IR Data (ATR, cm⁻¹): 2972 (w), 1681 (w), 1463 (w), 1390 (w), 1356 (w),1330 (w), 1290 (w), 1250 (w), 1160 (w), 1132 (w), 1066 (w), 918 (m), 889(s), 828 (s), 813 (s), 798 (s), 765 (m), 737 (vs), 684 (w), 647 (w), 561(w), 498 (s), 465 (m), 429 (w).

Preparation of {[Tism^(Pr) ^(i) ^(Benz)]Zn}[HB(C₆F₅)₃]

A solution of [κ³-Tism^(Pr) ^(i) ^(Benz)]ZnH (7.5 mg, 0.010 mmol) inbenzene (ca 0.5 mL) was added dropwise to a solution of B(C₆F₅)₃ (6 mg,0.012 mmol) in benzene (ca 0.5 mL). The solution was allowed to standfor 30 minutes, during which period, crystals suitable for X-raydiffraction were deposited. The colorless crystals of {[Tism^(Pr) ^(i)^(Benz)]Zn}[HB(C₆F₅)₃] were collected and washed with benzene (1 mL) andpentane (1 mL), and dried in vacuo (6 mg, 47%).

¹H NMR (C₆D₆):

0.27 [s, 18H, (C₆H₄N₂CH(CH₃)₂CSi(CH ₃)₂)₃CZnHB(C₆F₅)₃],

1.12 [d, J=7 Hz, 18H, (C₆H₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CZnHB(C₆F₅)₃],

4.46 [sep, J=7 Hz, 3H, (C₆H₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CZnHB(C₆F₅)₃],

6.97 [m, J=7 Hz, 3H, (C₆ H ₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CZnHB(C₆F₅)_(3],)

7.10 [m, 6H, (C₆ H ₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CZnHB(C₆F₅)₃],

7.78 [d, J=8 Hz, 3H, (C₆ H ₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CZnHB(C₆F₅)₃],

not observed [1H, (C₆H₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CZnHB(C₆F₅)₃].

¹H NMR (C₆D₅Br):

0.29 [s, 18H, (C₆H₄N₂CH(CH₃)₂CSi(CH ₃)₂)₃CZnHB(C₆F₅)₃],

1.35 [d, J=7 Hz, 18H, (C₆H₄N₂CH(CH ₃)₂CSi(CH₃)₂)₃CZnHB(C₆F₅)₃],

4.58 [sep, J=7 Hz, 3H, (C₆ H ₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CZnHB(C₆F₅)₃],

7.15 [t, J=7 Hz, 3H, (C₆ H ₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CZnHB(C₆F₅)₃],

7.23 [m, 3H, (C₆ H ₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CZnHB(C₆F₅)₃],

7.36 [d, J=8 Hz, 3H, (C₆ H ₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CZnHB(C₆F₅)₃],

7.90 [d, J=8 Hz, 3H, (C₆ H ₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CZnHB(C₆F₅)₃],

not observed [1H, (C₆H₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CZnHB(C₆F₅)₃].

¹³C{¹H} NMR (C₆D₅Br):

3.38 [s, 6C, (C₆H₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CZnHB(C₆F₅)₃],

20.92 [s, 6C, (C₆H₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CZnHB(C₆F₅)_(3],)

51.25 [s, 3C, (C₆H₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CZnHB(C₆F₅)_(3],)

113.77 [s, 3C, (C₆H₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CZnHB(C₆F₅)_(3],)

116.87 [s, 3C, (C₆H₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CZnHB(C₆F₅)_(3],)

124.24 [s, 3C, (C₆H₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CZnHB(C₆F₅)_(3],)

124.41 [s, 3C, (C₆H₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CZnHB(C₆F₅)_(3],)

133.44 [s, 3C, (C₆H₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CZnHB(C₆F₅)_(3],)

140.48 [s, 3C, (C₆H₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CZnHB(C₆F₅)_(3],)

167.09 [s, 3C, (C₆H₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CZnHB(C₆F₅)₃],

not observed/obscured by solvent[(C₆H₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CZnHB(C₆F₅)₃].

¹⁹F NMR (C₆D₅Br):

−166.22 [meta, m, 6F, (C₆H₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CZnHB(C₆ F ₅)₃],

−163.59 [para, t, J=21 Hz, 3F, (C₆H₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CZnHB(C₆ F₅)₃],

−131.84 [ortho, d, J=22 Hz, 6F, (C₆H₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CZnHB(C₆ F₅)₃].

²⁹Si NMR (C₆D₅Br): −4.48 [s, 3Si,(C₆H₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CZnHB(C₆F₅)₃].

¹¹B NMR (C₆D₅Br):

−24.5 [d, J=95 Hz, 1B, (C₆H₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CZnHB(C₆F₅)₃].

IR Data (ATR, cm⁻¹): 2975 (w), 1639 (w), 1508 (m), 1460 (s), 1403 (w),1371 (m), 1317 (w), 1298 (w), 1274 (w), 1260 (w), 1163 (w), 1102 (m),1068 (m), 968 (s), 922 (vs), 827 (s), 813 (m), 790 (m), 764 (m), 745(s), 700 (w), 678 (vs), 659 (m), 601 (w), 564 (m), 530 (w), 467 (w), 444(w), 434 (w), 405 (w).

Preparation of [Tism^(Pr) ^(i) ^(Benz)]Mg(κ²-O₂CH)

A solution of [Tism^(Pr) ^(i) ^(Benz)]MgH (20 mg, 0.029 mmol) in C₆D₆(ca 0.7 mL) was treated with CO₂ (1 atm), resulting in an immediatecolor change from yellow to colorless and the deposition of a whiteprecipitate over a period of 10 minutes. The precipitate was collectedand washed with benzene (3×1 mL) to give [Tism^(Pr) ^(i)^(Benz)]Mg(κ²-O₂CH) as a white powder (10 mg, 47% yield). Colorlesscrystals suitable for X-ray diffraction were obtained via slowevaporation from a concentrated benzene solution.

Anal. calcd. for [Tism^(Pr) ^(i) ^(Benz)]Mg(k²-O₂CH).C₆H₆: C, 65.1%; H,7.2%; N, 10.4%. Found: C, 64.4%; H, 6.9%; N, 9.9%.

¹H NMR (C₆D₆):

0.68 [s, 18H, (C₆H₄N₂CH(CH₃)₂CSi(CH ₃)₂)₃CMgOC(O)H],

1.10 [d, J=7 Hz, 18H, (C₆H₄N₂CH(CH ₃)₂CSi(CH₃)₂)₃CMgOC(O)H],

4.68 [sep, J=7 Hz, 3H, (C₆H₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CMgOC(O)H],

6.94 [t, J=8 Hz, 3H, (C₆ H ₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CMgOC(O)H],

7.08 [d, J=8 Hz, 3H, (C₆ H ₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CMgOC(O)H],

7.19 [t, J=8 Hz, 3H, (C₆ H ₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CMgOC(O)H],

8.87 [s, 1H, (C₆H₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CMgOC(O)H],

9.06 [d, J=8 Hz, 3H, (C₆ H ₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CMgOC(O)H].

¹³C{¹H} NMR (C₆D₆):

6.69 [s, 6C, (C₆H₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CMgOC(O)H],

21.00 [s, 6C, (C₆H₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CMgOC(O)H],

49.69 [s, 3C, (C₆H₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CMgOC(O)H],

112.45 [s, 3C, (C₆H₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CMgOC(O)H],

121.55 [s, 3C, (C₆H₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CMgOC(O)H],

122.46 [s, 3C, (C₆H₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CMgOC(O)H],

122.52 [s, 3C, (C₆H₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CMgOC(O)H],

134.13 [s, 3C, (C₆H₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CMgOC(O)H],

144.02 [s, 3C, (C₆H₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CMgOC(O)H],

166.06 [s, 3C, (C₆H₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CMgOC(O)H],

173.24 [s, 1C, (C₆H₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CMgOC(O)H],

not observed [(C₆H₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CMgOC(O)H].

²⁹Si NMR (C₆D₆): −10.36 [s, 3Si, (C₆H₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CMgOC(O)H].

IR Data (ATR, cm⁻¹): 1577 (m), 1465 (w), 1393 (w), 1356 (w), 1329 (w),1248 (w), 1067 (w), 939 (s), 905 (s), 828 (m), 815 (m), 795 (m), 764(w), 741 (s), 686 (m), 502 (m), 444 (w).

Preparation of {[Tism^(Pr) ^(i) ^(Benz)]Mg}[HB(C₆F₅)₃]

A solution of [Tism^(Pr) ^(i) ^(Benz)]MgH (10 mg, 0.015 mmol) in benzene(ca 0.5 mL) was added dropwise to a solution of B(C₆F₅)₃ (7.4 mg, 0.014mmol) in benzene (ca 0.5 mL). The solution was allowed to stand for 30minutes, during which period crystals suitable for X-ray diffractionwere deposited. The colorless crystals of {[Tism^(Pr) ^(i)^(Benz)]Mg}{HB(C₆F₅)₃} were collected and washed with benzene (1 mL) andthen pentane (1 mL), and dried in vacuo (6 mg, 34%).

¹H NMR (C₆D₆):

0.30 [s, 18H, (C₆H₄N₂CH(CH₃)₂CSi(CH ₃)₂)₃CMgHB(C₆F₅)₃],

1.18 [d, J=7 Hz, 18H, (C₆H₄N₂CH(CH ₃)₂CSi(CH₃)₂)₃CMgHB(C₆F₅)₃],

4.55 [sep, J=7 Hz, 3H, (C₆H₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CMgHB(C₆F₅)₃],

7.00 [t, J=7 Hz, 3H, (C₆ H ₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CMgHB(C₆F₅)₃],

7.11 [m, 6H, obscured by solvent, (C₆ H₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CMgHB(C₆F₅)₃],

7.73 [d, J=8 Hz, 3H, (C₆ H ₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CMgHB(C₆F₅)₃],

not observed [1H, (C₆H₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CMgHB(C₆F₅)₃].

¹⁹F NMR (C₆D₆):

−166.00 [meta, br, 6F, (C₆H₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CMgHB(C₆ F ₅)₃],

−163.49 [para, br, 3F, (C₆H₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CMgHB(C₆ F ₅)₃],

−131.30 [ortho, br, 6F, (C₆H₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CMgHB(C₆ F ₅)₃].

IR Data (ATR, cm⁻¹): 2946 (w), 1639 (w), 1508 (w), 1461 (s), 1405 (w),1360 (m), 1319 (w), 1276 (w), 1260 (w), 1161 (w), 1064 (m), 968 (m), 940(vs), 826 (s), 813 (s), 791 (m), 735 (s), 696 (w), 683 (w), 649 (w), 621(w), 561 (w), 543 (w), 531 (w), 502 (w), 443 (m).

Preparation of [Tism^(Pr) ^(i) ^(Benz)]MgOC(H)OB(C₆F₅)₃

Three preparation methods were employed:

(i) A suspension of [Tism^(Pr) ^(i) ^(Benz)]MgH (3 mg, 0.004 mmol) andB(C₆F₅)₃ (2.2 mg, 0.004 mmol) in benzene (0.7 mL) was treated with CO₂(1 atm). The sample was shaken intermittently and the mixture wasdecanted after 30 minutes to afford [Tism^(Pr) ^(i)^(Benz)]MgOC(H)OB(C₆F₅)₃ as a white powder (4 mg, 74%). Colorlesscrystals suitable for X-ray diffraction were obtained via vapordiffusion of pentane into a concentrated benzene solution.

(ii) A suspension of {[Tism^(Pr) ^(i) ^(Benz)]Mg}{HB(C₆F₅)₃} (8 mg,0.007 mmol) in C₆D₆ was treated with CO₂ (1 atm) and the immediateformation of [Tism^(Pr) ^(i) ^(Benz)]MgOC(H)OB(C₆F₅)₃ was demonstratedby ¹H NMR spectroscopy.

(iii) A suspension of [Tism^(Pr) ^(i) ^(Benz)]Mg(κ²-O₂CH) (3 mg, 0.004mmol) in C₆D₆ (ca 0.7 mL) was treated with B(C₆F₅)₃ (ca. 1.25 equiv.)and the formation of [Tism^(Pr) ^(i) ^(Benz)]MgOC(H)OB(C₆F₅)₃ wasdemonstrated by ¹H NMR spectroscopy.

¹H NMR (C₆D₆):

0.27 [s, 18H, (C₆H₄N₂CH(CH₃)₂CSi(CH ₃)₂)₃CMgO(H)COB(C₆F₅)₃],

1.10 [d, J=7 Hz, 18H, (C₆H₄N₂CH(CH ₃)₂CSi(CH₃)₂)₃CMgO(H)COB(C₆F₅)_(3],)

4.50 [sep, J=7 Hz, 3H, (C₆H₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CMgO(H)COB(C₆F₅)₃],

7.02 [m, 3H, (C₆ H ₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CMgO(H)COB(C₆F₅)₃],

7.13 [m, 6H, (C₆ H ₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CMgO(H)COB(C₆F₅)₃],

8.27 [d, J=7 Hz, 3H, (C₆ H ₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CMgO(H)COB(C₆F₅)₃],

8.76 [s, 1H, (C₆ H ₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CMgO(H)COB(C₆F₅)₃].

¹H NMR (C₆D₅Br):

0.24 [s, 18H, (C₆H₄N₂CH(CH ₃)₂CSi(CH₃)₂)₃CMgO(H)COB(C₆F₅)₃],

1.30 [d, J=7 Hz, 18H, (C₆H₄N₂CH(CH ₃)₂CSi(CH₃)₂)₃CMgO(H)COB(C₆F₅)₃],

4.64 [sep, J=7 Hz, 3H, (C₆H₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CMgO(H)COB(C₆F₅)₃],

7.08 [m, 6H, (C₆ H ₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CMgO(H)COB(C₆F₅)₃],

7.26 [m, 3H, (C₆ H ₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CMgO(H)COB(C₆F₅)_(3],)

8.14 [m, 3H, (C₆ H ₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CMgO(H)COB(C₆F₅)_(3],)

8.73 [s, 1H, (C₆ H ₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CMgO(H)COB(C₆F₅)₃].

¹³C{¹H} NMR (C₆D₅Br):

3.95 [s, 6C, (C₆H₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CMgO(H)COB(C₆F₅)₃],

20.78 [s, 6C, (C₆H₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CMgO(H)COB(C₆F₅)₃],

50.16 [s, 3C, (C₆H₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CMgO(H)COB(C₆F₅)₃],

112.58 [s, 3C, (C₆H₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CMgO(H)COB(C₆F₅)₃],

119.40 [s, 3C, (C₆H₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CMgO(H)COB(C₆F₅)₃],

122.72 [s, 3C, (C₆H₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CMgO(H)COB(C₆F₅)₃],

123.10 [s, 3C, (C₆H₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CMgO(H)COB(C₆F₅)₃],

133.56 [s, 3C, (C₆H₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CMgO(H)COB(C₆F₅)₃],

142.60 [s, 3C, (C₆H₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CMgO(H)COB(C₆F₅)₃],

167.38 [s, 3C, (C₆H₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CMgO(H)COB(C₆F₅)₃],

170.84 [s, 1C, (C₆H₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CMgO(H)COB(C₆F₅)₃],

not observed/obscured by solvent[(C₆H₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CMgO(H)COB(C₆F₅)₃].

¹⁹F NMR (C₆D₅Br):

−163.4 [meta, m, 6F, (C₆H₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CMgO(H)COB(C₆ F ₅)₃],

−157.6 [para, t, J=21 Hz, 3F, (C₆H₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CMgO(H)COB(C₆ F₅)₃],

−132.6 [ortho, m, 6F, (C₆H₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CMgO(H)COB(C₆ F ₅)₃].

²⁹Si NMR (C₆D₅Br): −10.71 [s, 3Si,(C₆H₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CMgO(H)COB(C₆F₅)₃].

¹¹B NMR (C₆D₅Br): −6.97 [b, 1B,(C₆H₄N₂CH(CH₃)₂CSi(CH₃)₂)₃CMgO(H)COB(C₆F₅)₃].

IR Data (ATR, cm⁻¹): 2945 (w), 1665 (s), 1645 (m), 1515 (m), 1461 (vs),1387 (m), 1373 (s), 1357 (m), 1321 (s), 1280 (m), 1259 (m), 1160 (m),1135 (w), 1095 (s), 1067 (m), 981 (s), 969 (s), 943 (vs), 916 (vs), 825(vs), 812 (vs), 791 (s), 783 (s), 775 (m), 764 (m), 751 (vs), 739 (vs),685 (s), 674 (vs), 616 (m), 602 (m), 577 (m), 560 (s), 531 (m), 514 (m),498 (m), 443 (s).

Example 3 Catalytic Hydrosilylation of Styrene

A general route to obtain the Markovnikov product, Ph(Me)C(H)SiH₂Ph, bythe hydrosilylation of styrene using [Tism^(Pr) ^(i) ^(Benz)]MgH ascatalyst, is illustrated below (Scheme 1). Detailed preparationsstarting from [Tism^(Pr) ^(i) ^(Benz)]MgMe (i) or [Tism^(Pr) ^(i)^(Benz)]MgH (ii) are also provided.

(i) A solution of phenylsilane (15 equiv, 0.107 mmol) and styrene (10equiv, 0.071 mmol) in C₆D₆ (0.7 mL), with mesitylene (2 equiv, 0.014mmol) as an internal standard, was added to [Tism^(Pr) ^(i) ^(Benz)]MgMe(5 mg, 0.007 mmol) in an NMR tube equipped with a J. Young valve. Thesolution was heated at 60° C. and monitored regularly by ¹H NMRspectroscopy, thereby demonstrating the formation of Ph(Me)C(H)SiH₂Ph bycomparison to literature data. Substrate consumption was complete in 10hours, after which point integration of the hydrosilylation product withrespect to mesitylene indicated a TOF of 0.9 h⁻¹.

(ii) A solution of phenylsilane (15 equiv, 0.044 mmol) and styrene (10equiv, 0.029 mmol) in C₆D₆ (0.7 mL) was added to [Tism^(Pr) ^(i)^(Benz)]MgH (2 mg, 0.003 mmol) in an NMR tube equipped with a J. Youngvalve. The solution was heated at 60° C. and monitored regularly by ¹HNMR spectroscopy, thereby demonstrating the formation ofPh(Me)C(H)SiH₂Ph.

Example 4 Catalytic Hydroboration of Styrene

A general route to obtain the Markovnikov product, Ph(Me)C(H)Bpin, bythe hydroboration of styrene using [Tism^(Pr) ^(i) ^(Benz)]MgH ascatalyst, is illustrated below (Scheme 2). Detailed preparationsstarting from [Tism^(Pr) ^(i) ^(Benz)]MgMe (i) or [Tism^(Pr) ^(i)^(Benz)]MgH (ii) are also provided.

(i) A solution of pinacolborane (15 equiv, 0.107 mmol) and styrene (10equiv, 0.071 mmol) in C₆D₆ (0.7 mL), with mesitylene (2 equiv, 0.014mmol) as an internal standard, was added to [Tism^(Pr) ^(i) ^(Benz)]MgMe(5 mg, 0.007 mmol) in an NMR tube equipped with a J. Young valve. Thesolution was heated at 60° C. and monitored regularly by ¹H NMRspectroscopy, thereby demonstrating the formation of Ph(Me)C(H)Bpin bycomparison to literature data, after removing volatile components andredissolving in CDCl₃. Substrate consumption was complete in 32 hours,after which point integration of the hydroboration product with respectto mesitylene indicated a TOF of 0.3 h⁻¹.

(ii) A solution of pinacolborane (15 equiv, 0.044 mmol) and styrene (10equiv, 0.029 mmol) in C₆D₆ (0.7 mL) was added to [Tism^(Pr) ^(i)^(Benz)]MgH (2 mg, 0.003 mmol) in an NMR tube equipped with a J. Youngvalve. The solution was heated at 60° C. and monitored regularly by ¹HNMR spectroscopy, thereby demonstrating the formation of Ph(Me)C(H)Bpin.

Example 5 Catalytic Hydrosilylation of Carbon Dioxide

The catalytic cycle for the hydrosilylation of CO₂ by magnesium or zincsystem is summarized below (Scheme 3). Exemplary preparations are alsoprovided. Selected results are shown in Table 1.

Magnesium System:

(a) A solution of PhSiH₃ (0.14 mmol) and mesitylene in C₆D₆ (ca 0.5 mL)was added to a mixture of [Tism^(Pr) ^(i) ^(Benz)]MgH (0.0028 mmol) andB(C₆F₅)₃ (0.014 mmol) in an NMR tube equipped with a J. Young valve. Thesample was treated with CO₂ (1 atm) and monitored by ¹H and ¹⁹F NMRspectroscopy. Products were identified by comparison to literaturevalues and TONs were determined by integration with respect to themesitylene internal standard.

(b) A solution of Et₃SiH (0.14 mmol) and mesitylene in C₆D₆ (ca 0.5 mL)was added to a mixture of [Tism^(Pr) ^(i) ^(Benz)]MgH (0.0028 mmol) andB(C₆F₅)₃ (0.014 mmol) in an NMR tube equipped with a J. Young valve. Thesample was treated with CO₂ (1 atm) and monitored by ¹H and ¹⁹F NMRspectroscopy. Products were identified by comparison to literaturevalues and TONs were determined by integration with respect to themesitylene internal standard.

(c) A solution of Ph₃SiH (0.14 mmol) and mesitylene in C₆D₆ (ca 0.5 mL)was added to a mixture of [Tism^(Pr) ^(i) ^(Benz)]MgH (0.0028 mmol) andB(C₆F₅)₃ (0.014 mmol) in an NMR tube equipped with a J. Young valve. Thesample was treated with CO₂ (1 atm) and monitored by ¹H and ¹⁹F NMRspectroscopy. Products were identified by comparison to literaturevalues and TONs were determined by integration with respect to themesitylene internal standard.

(d) A solution of PhSiH₃ (1.42 mmol), [Tism^(Pr) ^(i) ^(Benz)]MgH (0.007mmol), B(C₆F₅)₃ (0.035 mmol) and mesitylene in C₆D₆ (ca 1.5 mL) in anampoule was treated with CO₂ (1 atm) and the products were analyzedafter a period of 14 hours by comparison to the literature NMR data andTONs were determined by integration with respect to the mesityleneinternal standard.

(e) A solution of Et₃SiH (1.42 mmol), [Tism^(Pr) ^(i) ^(Benz)]MgH (0.007mmol), B(C₆F₅)₃ (0.035 mmol) and mesitylene in C₆D₆ (ca 1.5 mL) in anampoule was treated with CO₂ (1 atm) and the products were analyzedafter a period of 70 hours by comparison to the literature NMR data andTONs were determined by integration with respect to the mesityleneinternal standard.

(f) A solution of Ph₃SiH (1.42 mmol), [Tism^(Pr) ^(i) ^(Benz)]MgH (0.007mmol), B(C₆F₅)₃ (0.035 mmol) and mesitylene in C₆D₆ (ca 1.5 mL) in anampoule was treated with CO₂ (1 atm) and the products were analyzedafter a period of 70 hours by comparison to the literature NMR data andTONs were determined by integration with respect to the mesityleneinternal standard.

(g) A solution of PhSiH₃ (0.14 mmol) and mesitylene in C₆D₆ (ca 0.5 mL)was added to a mixture of [Tism^(Pr) ^(i) ^(Benz)]MgMe (0.0028 mmol) andB(C₆F₅)₃ (0.014 mmol) in an NMR tube equipped with a J. Young valve. Thesample was treated with CO₂ (1 atm) and monitored by ¹H and ¹⁹F NMRspectroscopy. Products were identified by comparison to literaturevalues and TONs were determined by integration with respect to themesitylene internal standard.

(h) A solution of Et₃SiH (0.14 mmol) and mesitylene in C₆D₆ (ca 0.5 mL)was added to a mixture of [Tism^(Pr) ^(i) ^(Benz)]MgMe (0.0028 mmol) andB(C₆F₅)₃ (0.014 mmol) in an NMR tube equipped with a J. Young valve. Thesample was treated with CO₂ (1 atm) and monitored by ¹H and ¹⁹F NMRspectroscopy. Products were identified by comparison to literaturevalues and TONs were determined by integration with respect to themesitylene internal standard.

(i) A solution of Ph₃SiH (0.14 mmol) and mesitylene in C₆D₆ (ca 0.5 mL)was added to a mixture of [Tism^(Pr) ^(i) ^(Benz)]MgMe (0.0028 mmol) andB(C₆F₅)₃ (0.014 mmol) in an NMR tube equipped with a J. Young valve. Thesample was treated with CO₂ (1 atm) and monitored by ¹H and ¹⁹F NMRspectroscopy. Products were identified by comparison to literaturevalues and TONs were determined by integration with respect to themesitylene internal standard.

(j) A solution of PhSiH₃ (1.42 mmol), [Tism^(Pr) ^(i) ^(Benz)]MgMe(0.007 mmol), B(C₆F₅)₃ (0.035 mmol) and mesitylene in C₆D₆ (ca 1.5 mL)in an ampoule was treated with CO₂ (1 atm) and the products wereanalyzed after a period of 14 hours by comparison to the literature NMRdata and TONs were determined by integration with respect to themesitylene internal standard.

(k) A solution of Et₃SiH (1.42 mmol), [Tism^(Pr) ^(i) ^(Benz)]MgMe(0.007 mmol), B(C₆F₅)₃ (0.035 mmol) and mesitylene in C₆D₆ (ca 1.5 mL)in an ampoule was treated with CO₂ (1 atm) and the products wereanalyzed after a period of 72 hours by comparison to the literature NMRdata and TONs were determined by integration with respect to themesitylene internal standard.

(l) A solution of Ph₃SiH (1.42 mmol), [Tism^(Pr) ^(i) ^(Benz)]MgMe(0.007 mmol), B(C₆F₅)₃ (0.035 mmol) and mesitylene in C₆D₆ (ca 1.5 mL)in an ampoule was treated with CO₂ (1 atm) and the products wereanalyzed after a period of 72 hours by comparison to the literature NMRdata and TONs were determined by integration with respect to themesitylene internal standard.

(m) A solution of PhSiH₃ (0.14 mmol) in C₆D₆ (ca 0.5 mL) was added to amixture of [Tism^(Pr) ^(i) ^(Benz)]MgMe (0.0014 mmol) and B(C₆F₅)₃(0.0078 mmol) in an NMR tube equipped with a J. Young valve. The samplewas treated with CO₂ (1 atm) and monitored by ¹H spectroscopy. Uponcomplete consumption of PhSiH₃, CH₄ and excess CO₂ were removed via afreeze-pump-thaw cycle. The sample was then reloaded with PhSiH₃ (0.14mmol) and CO₂ (1 atm), and the process was repeated for a cumulativetotal of 8 cycles of silane consumption without any substantial loss ofactivity.

Zinc System:

(a) A solution of PhSiH₃ (0.037 mmol) and mesitylene in C₆D₅Br (ca 0.5mL) was added to a mixture of {[Tism^(Pr) ^(i) ^(Benz)]Zn}[HB(C₆F₆)₃](0.0008 mmol) and B(C6F5)3 (0.002 mmol) in an NMR tube equipped with aJ. Young valve. The sample was treated with CO₂ (1 atm) and monitored by¹H and ¹⁹F NMR spectroscopy. Products were identified by comparison toliterature values and TONs were determined by integration with respectto the mesitylene internal standard.

(b) A solution of Et₃SiH (0.014 mmol) and mesitylene in C₆D₅Br (ca 0.5mL) was added to a mixture of {[Tism^(Pr) ^(i) ^(Benz)]Zn}[HB(C₆F₆)₃](0.0028 mmol) and B(C₆F₅)₃ (0.0011 mmol) in an NMR tube equipped with aJ. Young valve. The sample was treated with CO₂ (1 atm) and monitored by¹H and ¹⁹F NMR spectroscopy. Products were identified by comparison toliterature values and TONs were determined by integration with respectto the mesitylene internal standard.

(c) A solution of Ph₃SiH (0.014 mmol) and mesitylene in C₆D₅Br (ca 0.5mL) was added to a mixture of {[Tism^(Pr) ^(i) ^(Benz)]Zn}[HB(C₆F₆)₃](0.0028 mmol) and B(C₆F₅)₃ (0.0011 mmol) in an NMR tube equipped with aJ. Young valve. The sample was treated with CO₂ (1 atm) and monitored by¹H and ¹⁹F NMR spectroscopy. Products were identified by comparison toliterature values and TONs were determined by integration with respectto the mesitylene internal standard.

(d) A solution of PhSiH₃ (0.11 mmol) in C₆D₆ (ca 0.5 mL) was added to amixture of [Tism^(Pr) ^(i) ^(Benz)]ZnH (0.0027 mmol) and B(C₆F₅)₃ (0.055mmol) in an NMR tube equipped with a J. Young valve. The sample wastreated with CO₂ (1 atm) and monitored by ¹H and ¹⁹F NMR spectroscopy,thereby demonstrating the catalytic conversion to CH₄.

TABLE 1 Selected results for catalytic hydrosilylation of CO₂. TON^(b)catalyst^(a) R₃SiH product (TOF/h⁻¹) [Mg] (0.5%)/[B] (2.5%)^(c) PhSiH₃CH₄ 542, 416^(d) (38.7, 29.7)^(d) [Mg] (0.5%)/[B] (2.5%)^(c) Ph₃SiHH₃C(OSiPh₃)₂  83, 178^(d) (1.2, 2.5)^(d) [Zn] (2.5%)/[B] (5.0%)^(e)PhSiH₃ CH₄ 117 (0.8)   [Zn] (2.0%)/[B] (10.0%)^(e) Ph₃SiH H₂C(OSiPh₃)₂12 (0.1)  ^(a)[Mg] = [Tism^(Pr) ^(i) ^(Benz)]MgH or [Tism^(Pr) ^(i)^(Benz)]MgMe; [Zn] = {[Tism^(Pr) ^(i) ^(Benz)] − Zn}[HB(C₆F₅)₃]; [B] =B(C₆F₅)₃. ^(b)Number of Si—H bonds consumed per metal. ^(c)C₆D₆.^(d)Values for [Tism^(Pr) ^(i) ^(Benz) ]MgH listed first. ^(e)C₆D₅Br.

Example 6 Preparation of Formaldehyde Equivalent from Carbon Dioxide

A general route to obtain a formaldehyde equivalent from CO₂ using themetal complexes disclosed herein as catalyst is illustrated below(Scheme 4). Detailed preparation is also provided.

Exemplary procedures are provided below.

(a) A solution of Ph₃SiH (0.14 mmol) and mesitylene in C₆D₆ (ca 0.5 mL)was added to a mixture of [Tism^(Pr) ^(i) ^(Benz)]MgH (0.0028 mmol) andB(C₆F₅)₃ (0.014 mmol) in an NMR tube equipped with a J. Young valve. Thesample was treated with CO₂ (1 atm) and monitored by ¹H and ¹⁹F NMRspectroscopy. Products were identified by comparison to literaturevalues and TONs were determined by integration with respect to themesitylene internal standard.

(b) A solution of Ph₃SiH (1.42 mmol), [Tism^(Pr) ^(i) ^(Benz)]MgH (0.007mmol), B(C₆F₅)₃ (0.035 mmol) and mesitylene in C₆D₆ (ca 1.5 mL) in anampoule was treated with CO₂ (1 atm) and the products were analyzedafter a period of 70 hours by comparison to the literature NMR data andTONs were determined by integration with respect to the mesityleneinternal standard.

(c) A solution of Ph₃SiH (0.14 mmol) and mesitylene in C₆D₆ (ca 0.5 mL)was added to a mixture of [Tism^(Pr) ^(i) ^(Benz)]MgMe (0.0028 mmol) andB(C₆F₅)₃ (0.014 mmol) in an NMR tube equipped with a J. Young valve. Thesample was treated with CO₂ (1 atm) and monitored by ¹H and ¹⁹F NMRspectroscopy. Products were identified by comparison to literaturevalues and TONs were determined by integration with respect to themesitylene internal standard.

(d) A solution of Ph₃SiH (1.42 mmol), [Tism^(Pr) ^(i) ^(Benz)]MgMe(0.007 mmol), B(C₆F₅)₃ (0.035 mmol) and mesitylene in C₆D₆ (ca 1.5 mL)in an ampoule was treated with CO₂ (1 atm) and the products wereanalyzed after a period of 72 hours by comparison to the literature NMRdata and TONs were determined by integration with respect to themesitylene internal standard.

Example 7 Use of Metal Complexes to Reduce Carbon Monoxide

A catalyst is treated with carbon monoxide (1 atm) and 10-1000equivalents of a hydrosilane (R₃SiH) or hydroborane (R₂BH), resulting inthe catalytic formation of the reduced species.

Example 8 Catalytic Hydrogenation of Alkenes/Alkynes

A catalyst is treated with hydrogen (1-20 atm) and 10-1000 equivalentsof an alkene or alkyne, resulting in the catalytic formation of thehydrogenated species.

Example 9 Catalytic Polymerization of Alkenes

A catalyst is treated with an alkene (10-1000 equivalents), resulting inthe catalytic formation of the polymerized species.

Example 10 Catalytic Production of Hydrogen-on-demand fromAlcohols/Amines

A catalyst is treated with an alcohol or primary or secondary amine(10-1000 equivalents) and 10-1000 equivalents of a hydrosilane (R₃SiH)or hydroborane (R₂BH), resulting in the catalytic formation of hydrogen.

Example 11 Catalytic Hydrosilylation of Ketones/Aldehydes

A catalyst is treated with a ketone or aldehyde (10-1000 equivalents)and 10-1000 equivalents of a hydrosilane (R₃SiH) or hydroborane (R₂BH),resulting in the catalytic formation of the corresponding hydrosilylatedor hydroborated products.

Example 12 Tishchenko Reaction Using Metal Complexes

A catalyst is treated with an aldehyde (10-1000 equivalents), resultingin the catalytic formation of the corresponding ester.

Example 13 Catalytic Hydrogenation of Carbon Dioxide

A catalyst is treated with carbon dioxide (1-20 atm) and hydrogen (1-20atm) resulting in the catalytic formation of a hydrogenated species suchas, e.g., methanol, formic acid, methane, formaldehyde, etc.

Example 14 Catalytic Hydrogenation of Carbon Monoxide

A catalyst is treated with carbon monoxide (1-20 atm) and hydrogen (1-20atm) resulting in the catalytic formation of a hydrogenated species suchas, e.g., methanol, formic acid, methane, formaldehyde, etc.

DOCUMENTS CITED

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Four Appendices (A to D) are attached hereto which provide additionaldetails regarding the inventive principles described in this disclosure.The Appendices are expressly incorporated herein by reference in theirentireties. In the event of a conflict between the teachings of thisapplication and those of the incorporated Appendices, the teachings ofthis application control.

All documents cited in this application are hereby incorporated byreference as if recited in full herein.

Although illustrative embodiments of the present invention have beendescribed herein, it should be understood that the invention is notlimited to those described, and that various other changes ormodifications may be made by one skilled in the art without departingfrom the scope or spirit of the invention.

What is claimed is:
 1. A multidentate ligand having the structure offormula (I):

wherein: Z is a linker group; R₁ is selected from the group consistingof H, halide, alkyl, aryl, aralkyl, heteroalkyl, heteroaryl, alkoxy,hydroxy, heteroalkoxy, amino, alkylamino, arylamino, cyano, nitro,sulfonyl, or a heterocyclic group; R₂ and R₃ are independently selectedfrom the group consisting of H, halide, alkyl, aryl, aralkyl,heteroalkyl, heteroaryl, alkoxy, hydroxy, heteroalkoxy, amino,alkylamino, arylamino, cyano, nitro, sulfonyl, or a heterocyclic group;or together form a saturated or unsaturated C₅₋₇ homocyclic orheterocyclic ring, wherein the ring is optionally substituted withgroups selected from H, halide, alkyl, aryl, aralkyl, heteroalkyl,heteroaryl, alkoxy, hydroxy, heteroalkoxy, amino, alkylamino, arylamino,cyano, nitro, sulfonyl, or a heterocyclic group.
 2. The multidentateligand of claim 1, wherein Z comprises a silicon-containing group. 3.The multidentate ligand of claim 1, wherein Z is Si(R₄)₂; and wherein R₄is selected from the group consisting of H, halide, alkyl, aryl,aralkyl, heteroalkyl, heteroaryl, alkoxy, hydroxy, heteroalkoxy, amino,alkylamino, arylamino, cyano or a heterocyclic group.
 4. Themultidentate ligand according to claim 1, having the followingstructure:


5. A method of preparing a metal complex, comprising coordinating theligand according to claim 1 to a metal center via a combination of up tothree nitrogen donors and the carbon atom.
 6. The method of claim 5,wherein the metal center comprises an atom selected from the main groupmetals, transition metals, or lanthanoids.
 7. The method of claim 5,wherein the metal center comprises an atom selected from Li, Mg, Ca, Fe,Ni, Cu, Zn, Zr and Cd.
 8. A metal complex prepared by the method ofclaim 5, the metal complex having the structure of formula (II):

wherein: M is an atom selected from Li, Mg, Ca, Fe, Ni, Cu, Zn, Zr andCd; and X is selected from no atom, H, Me, halogen, O₂CH, S₂CH, SH,N(H)Ph, CH(Me)Ph, O₂CMe and S₂CMe.
 9. A metal complex prepared by themethod of claim 5, the metal complex having a structure selected fromthe group consisting of:


10. A metal complex prepared by the method of claim 5, the metal complexhaving the following structure:


11. A metal complex prepared by the method of claim 5, the metal complexhaving the following structure:


12. A catalyst comprising at least one metal complex according to anyone of claims 8-11.
 13. A method of catalyzing hydrosilylation ofstyrenes, comprising providing the catalyst of claim 12 to ahydrosilylation reaction of a styrene.
 14. A method of catalyzinghydroboration of styrenes, comprising providing the catalyst of claim 12to a hydroboration reaction of a styrene.
 15. A method of catalyzinghydrosilylation of carbon dioxide, comprising providing the catalyst ofclaim 12 to a hydrosilylation reaction of carbon dioxide.
 16. A methodof preparing a formaldehyde equivalent from carbon dioxide comprisingcontacting a reaction mixture comprising carbon dioxide and a silanewith a compound prepared from the multidentate ligand of claim 1,wherein the silane is R₃SiH and R is selected from H, alkyl and aryl.17. The method of claim 16, wherein the multidentate ligand has thestructure:


18. The method of claim 16, wherein the compound comprises at least onemetal complex according to any one of claims 8-11.
 19. A method ofreducing carbon monoxide comprising contacting a reaction mixturecomprising carbon monoxide with a compound prepared from themultidentate ligand of claim
 1. 20. The method of claim 19, wherein themultidentate ligand has the structure:


21. The method of claim 19, wherein the compound comprises at least onemetal complex according to any one of claims 8-11.
 22. A method ofcatalyzing hydrogenation of alkenes or alkynes, comprising providing thecatalyst of claim 12 to a hydrogenation reaction of an alkene or analkyne.
 23. A method of catalyzing polymerization of alkenes, comprisingproviding the catalyst of claim 12 to a polymerization reaction ofalkenes.
 24. A method of catalyzing production of hydrogen-on-demandfrom alcohols or amines, comprising providing the catalyst of claim 12to the reaction.
 25. A method of catalyzing hydrosilylation of ketonesor aldehydes, comprising providing the catalyst of claim 12 to ahydrosilylation reaction of a ketone or an aldehyde.
 26. A method ofcatalyzing Tishchenko reaction, comprising providing the catalyst ofclaim 12 to the reaction.
 27. A method of catalyzing hydrogenation ofcarbon dioxide, comprising providing the catalyst of claim 12 to ahydrogenation reaction of carbon dioxide.
 28. A method of catalyzinghydrogenation of carbon monoxide, comprising providing the catalyst ofclaim 12 to a hydrogenation reaction of carbon monoxide.